Premium or Regular Gas?

[jimdogs]

Does anyone know if it really makes that much of a difference if you use 87, 89 or 91 Octane Gasoline in the new CX-7? Will it cause damage or just performance problems? thanks jim

[G-Papi]

Does anyone know if it really makes that much of a difference if you use 87, 89 or 91 Octane Gasoline in the new CX-7? Will it cause damage or just performance problems? thanks jim
I've used one tank of mid-grade (89 octane) and I noticed that the insides of those bright exhaust pipes are sooty looking, in spite of my rather aggressive driving style. Won't do that again!

I'm afraid to use 87 octane for fear of detonation (pinging, spark knocking, or whatever name you know it by).

[ChopstickHero]

what does it say in the CX7 manual? i'm guessing Premium.

[stangmatt66]

Does anyone know if it really makes that much of a difference if you use 87, 89 or 91 Octane Gasoline in the new CX-7? Will it cause damage or just performance problems? thanks jim

Somewhere Mazda has said that using 87 will force the engine into "emergency mode." I'd say stick with the recommended 91, especially if you bought the car and don't want to find out what "emergency mode" is.

[080669]

The manual specifies 91, so I've only put in premium. The inside of my tailpipes look sooty too, though. It might be because of the chemicals burning off the engine or something? I dunno...

[smo0f]

isnt the cx7 turbo charged?

[stangmatt66]

isnt the cx7 turbo charged?

yup and turbo engines love the premium!

[ZoomZoomH]

it's the same basic engine as the mazdaspeed 6, and that car REQUIRES premium, so put premium in there!

[doctor_r]

Turbo or SC on any vehicle = Premium Gas

[Vision67]

Does anyone know if it really makes that much of a difference if you use 87, 89 or 91 Octane Gasoline in the new CX-7? Will it cause damage or just performance problems? thanks jim

This engine has a big compression ratio. Premium fuel is part of the design.

If you can't afford premium, buy a Mazda 3 instead.

No such thing as a free lunch!

[jimdogs]

Thanks for the info!

[MazKid]

"Emergency mode" happens if the engine senses less than 91 octane...cuts boost by 30%. That's what I've heard.

[Zoom5Zoom]

Premium fuel is for the turbo engine......if you use regular fuel you reduce your HP by shit loads.....

BTW to run premium fuel based on 20000 km per year it costs you only 60 cents a day (cdn bux eh)

[cruzdreamer]

I have an RX 8 and granted it's a rotary engine but I have to say stick with the premium. When I put midgrade in it it really acts up...loses power, idles rough etc. With a turbo I bet it really needs the premium. I know gas prices stink and I tried midgrade for awhile and nothing but problems....I took it in and they found no issues and mentioned it's probably the gas...I did not have the heart to say I have been using mid grade off and on. I am considering a CX7 for my next vehicle so this topic interested me. Enjoy the CX7 folks!!! It was a blast to drive!

[stillflat4]

If you wanna see what lower octane gasoline does to this engine, just do a search in the Mazdaspeed6 board for "power loss." Not good. I've had it happen to me twice in my Speed6, even with 93 octane. Word is there's a software upgrade for it now that will fix it so that the knock sensor isn't so overzealous.

What happened is something along the lines of the engine protecting itself as soon as it detects even a hint of detonation, and it dramatically lowers the boost (actually, I believe it cuts the throttle by a significant amount).

Trust me, you don't want to try anything under 91, and I'd highly suggest you use 93 if you can get it.

As for the CX-7, I'm trying to slowly convince my wife that when we're ready to turn in her Forester in another 20-30K miles, she needs to get one of these. :)

The difficulty is going to be convincing her that it will be as reliable as the only-scheduled-maintenance-needed Subaru (almost 70K miles and nothing other than scheduled maintenance, knock on wood). My Speed6 has already been in the shop twice for different things in 4500 miles.

[080669]

Trust me, you don't want to try anything under 91, and I'd highly suggest you use 93 if you can get it.

So, you're saying given a choice between 91 and 93, put in 93?

[stillflat4]

So, you're saying given a choice between 91 and 93, put in 93?

I would. I am sure Mazda is releasing the CX-7 with the update that the new MS6 firmware provides. Mazda recommends 91 or above with the MS6, but most of us needed to use 93 (if we're in an area of the country that can get it) to avoid the oversensitive knock sensor from being tripped. I have just made it a matter of fact to get 93, and I think if you asked over on the MS6 forum, most of the people over there do the same.

I doubt you will need to be that careful with the CX-7, since hopefully Mazda learned a little about American gasoline. There's some site out there that lists the highest quality gasolines based upon quality control and cleaning power. I forget where it is, maybe someone here knows where it is. I looked at the list and the only distributor on the list here in NY was Shell, so I started using that exclusively (and got a shell gas card that I use JUST for gasoline -- $30 in rebates so far, and it takes the hit out of the extra I spend on premium fuel). I know Chevron is on the list too, but I forget what other companies are on there.

Sorry to go on... I think the point is that if you use quality fuels, I think you'll be all right with 91, but my earlier point was that you do NOT want to tempt "emergency mode" by using anything less. If it was my car, I would use 93. I wouldn't bother with 94 even if I could get it here (Sunoco stopped selling it here a few years ago).

I know some people claim that all gasoline comes from the same tankers, no matter the brand. I don't think that's true, and no one has shown me otherwise.

That said, I'm still open to convincing. :)

[wongpres]

There's some site out there that lists the highest quality gasolines based upon quality control and cleaning power. I forget where it is, maybe someone here knows where it is.

stillflat4's probably referring to Top Tier Gasoline:

http://www.toptiergas.com/

[stillflat4]

stillflat4's probably referring to Top Tier Gasoline:

http://www.toptiergas.com/

That was it, yes!! Thanks for the link!!

[Kansei]

hmm *bump*

I want to be using "top tier" gasoline but I don't believe any of those retailers are in my area :'(

In Rochester, NY I am able to go to:
Sunoco
Citgo
Exxon/Mobil (I refuse to go there, filthy bastards www.exxposeexxon.org)
Hess
BJs
Delta Sonic (I think it's sorta a local chain)
... pretty much just local places other than that.

There might be a "kwikfill" but I'm not sure. I know on the New York State Thruway there is ONLY Exxon or Sunoco, and pretty much going in one direction (east or west, I can't remember right now) you can only get Sunoco, in the other only Exxon.

:( I want to be putting clean gas in my car, what to do?

[G-Papi]

Find out who the jobbers are for the independents in your area. It may be that they're getting good gas. You never know until you find out who their suppliers (jobbers) are. If my terminology is off, the concept isn't).

[Kansei]

:'( I wish the independent stations were like.. at least somewhere near me haha

[bigfootxx2]

so something like you can save about 10% onthe cost of fuel but it is going to cost you 30% of the mpg you get in my case 23mpg down to 16 mpg not to mention a 30% power loss to. It seem like I going to put the 91 octane in.

[singlemalt_18]

Although the dealership said that you could run 2 tanks of mid after every 1 tank of premium, I'm not so keen on the idea - at least until I have a much more intimate familiarity with the performance of the engine.

Keep in mind that our CX-7 is not an everyday car... so I'm not at the gas pumps every other day, but I have been using a 50/50 mix of the mid 89, and the premium 93 when I fill up. The blending not only creates the recommended 91 octane, but also saves a little money - about a buc or so, but its someting.

I've got about 1000 miles so far... I have been flexing rpms into the 5000 - 6300 range periodically during the break-in, and I have not experienced any detonation, or other quirks. I continue to be amazed at the performance of this vehicle. Its a 4 cylinder that drives like a V8 - no matter where you are, all you need to do is touch the pedal a little to access everything it keeps in reserve.

First two fill-ups, and I have gotten 18.9 and 19.4 mpg - and that is not by driving efficiently.

[Kansei]

More info on "top tier" gas from about.com (yes, more info about the retailers than just the pathetic list on the official site:

Chevron: Chevron has markets in 29 states in the West, Southwest and South, as well as in Alaska and Hawaii. ALL grades of Chevron with Techron gasoline meet TOP TIER Detergent Gasoline Standards. QuikTrip: (Not to be confused with Kwik Trip). QuikTrip operates convenience stores and travel centers in a number of metropolitan areas:
Tulsa, OK
Springfield, MO
Kansas City, MO
Kansas City, KS
Wichita, KS
Des Moines, IA
Omaha, NE
St. Louis, MO
St. Louis, IL
Atlanta, GA
Dallas-Ft. Worth, TX
Phoenix, AZ
Bartlesville, OK
Miami, OK
Vinita, OK
Columbia, MOKwik Trip: (Not to be confused with QuikTrip). Over 450 Kwik Trip, Kwik Star, Hearty Platter® and Tobacco Outlet Plus stores throughout Wisconsin, Minnesota and Iowa.
Conoco: Conoco has over 4,000 stations located in 33 states.
Phillips 66: Phillips 66 has locations in 32 states across the nation.
76: 76 has over 2,700 stations located throughout the country.
Shell: Shell Oil Products has a network of nearly 7,000 branded gasoline stations in the Western United States. Shell Oil Company markets branded products through more than 10,000 stations in the Eastern and Southern United States.
Entec: Entec Stations offer gasoline through stations located in the greater Montgomery, Alabama area.
MFA: MFA Oil Company offers gasoline at "Break Time" convenience stores located throughout Missouri.


Anyone else notice that not a single entry on this list is in the Northeast??? :bs::bs:

ARGHARGH. It sucks though because I know shell is in the northeast (I've seen one.. just one.. in CT before) but their store locater web site (www.localshell.com) is down currently.

[tdf2001]

I have used 90 rated 90% gas/10% ethanol mix once (see my thread from a month ago). I had no problems whatsoever.

[Kansei]

I have used 90 rated 90% gas/10% ethanol mix once (see my thread from a month ago). I had no problems whatsoever.

That's what ALL the fuel is here. :(

[basunnyday]

Need a quick answer here. Bought a cx7 yesterday from a dealer 200 miles away. They are to deliver it to me next week. This is my first Foreign car or turbocharged. I didn't even think of it having to use premium gas. Not a mention of it from the salesman (pissed) Got home and started research, and figured out it needs premium. My problem is the highest octane offered for at least 60 miles is an ethanol blend with an 89 octane. Called the salesman about my problem, he didn't believe me and starting calling all the stations. Finally he agreed. Here is my problem, I'm into the contract but will be unable to put 91+ in the car except in rare case while traveling. Has any one ran the 89 octane, and what happens? Is fuel additives an option? . I really wanted the car, should I try to see how it runs on that fuel or try to negotiate out of my contract. Already have Mazda financing, so I may be stuck with a different kind of Mazda I don't want. HELP

[CXRabbit]

It NEEDS 91+ octane Bas... Not only will you potentially has misfire problems with lower, but the dealer could void your warranty.

[Sveivo]

Need a quick answer here. Bought a cx7 yesterday from a dealer 200 miles away. They are to deliver it to me next week. This is my first Foreign car or turbocharged. I didn't even think of it having to use premium gas. Not a mention of it from the salesman (pissed) Got home and started research, and figured out it needs premium. My problem is the highest octane offered for at least 60 miles is an ethanol blend with an 89 octane. Called the salesman about my problem, he didn't believe me and starting calling all the stations. Finally he agreed. Here is my problem, I'm into the contract but will be unable to put 91+ in the car except in rare case while traveling. Has any one ran the 89 octane, and what happens? Is fuel additives an option? . I really wanted the car, should I try to see how it runs on that fuel or try to negotiate out of my contract. Already have Mazda financing, so I may be stuck with a different kind of Mazda I don't want. HELP
Doesn't it ping with 89? I would not run 89 in that car.

[basunnyday]

Doesn't it ping with 89? I would not run 89 in that car.

I don't have the car yet. They are suppose to deliver it this week to me. So I don't know that was my question. Referring to the warranty. Using a lower octane will not void the warranty. I checked that out.

[UpNorth]

I found myself in a similar situation. I learned after my purchase that the best premium fuel offered in Alaska is 90. I assume that the car would perform better with 91, but it seems to be doing fine with the 90. My dealer assured me it should be fine. I don't know if droppping down another notch would make a significant difference.

I'll leave that to others who know more to answer.

I'm glad you confirmed that you won't have warrantee issues if you are stuck using 89 most of the time.

[erhayes]

The question of minimum octane requirement should go to the Mazda factory and NOT to a service writer or self appointed expert.

[Brian MP5T]

91 Minimum.

Don't buy a Turbo SUV and then cheap out on gas.

[mikey1981]

heres teh thing. If when you get your car delivered and u fill up with lower than 91 octane rating, anything that happens as a result, in terms of service you will most definately need, MAzda does not recognize this as warranty service. Everytime your car (and it will) misfire, not run properly, have detonation with the strong possibility of the car's computer shutting off the car to protect the engine, you will be paying thru the nose for service due to the lack of required gasonline.

if the situation you are talking about is in fact true, the inability to put in the required rating of gas, you should not take delivery of this car and/or swap it out for another vehicle. its not a question of if you'll have problems, its just a matter of when.

[mikey1981]

and dont take this the wrong way, but given the specs on the Mazda and the fact that its turbo car, let alone suv, u should have been a little more inquisitive as to what grade of gas goes in it. Not only that, this def should have popped up in your research BEFORE you bought the car.

[erhayes]

I'm sorry but, Mazda should not sell vehicles that require 91 octane gas where there is none. I said before, contact Mazda for the answer to the question as to whether 91 is mandatory or not. Hearsay and service writers may not be your best sourse of information. Do this BEFORE you take deleivery. JMO Ed

[basunnyday]

I'm sorry but, Mazda should not sell vehicles that require 91 octane gas where there is none. I said before, contact Mazda for the answer to the question as to whether 91 is mandatory or not. Hearsay and service writers may not be your best sourse of information. Do this BEFORE you take deleivery. JMO Ed

Thank you for being understanding. I doubt if I will take delivery,(unless Mazda tells me it will be fine) and hope that the dealership does not make a big fuss out of it. The salesman knew that I lived in a rural area. Heck they were delivering it to me. Never a mention on the premium gas in a four hour period during negotiations. I live in Nebraska, now I have researched the premium gas thing well. It is nearly impossible to get it except along I-80. That leaves a lot of Nebraska being many miles away from premium. Kansas and Eastern Colorado have the same issues in rural areas. I plan on talking to Mazda before making a final decision. All I know is that I can't drive a 120 round trip to fuel up.

As for the post before, saying that I should have did my research. I have been shopping for several months, but only briefly looked at the Mazda site. I looked at the specifications, it does not have anything on it about premium gas. The brochure would not download.

I accidently found the Mazda, liked the styling, took a drive, liked it, worked out what I considered a fair deal. Picked out a loaded GT model with all the option except the navigation package, at $3,000-$9,000 lower than comparable cars. Why would I even consider that it would require special gas, I think the power of the engine is very comparable to the V-6 edge. None of the other comparables require premium. The fact that it has a turbo may mean something some of you, the fact is the horsepower is similar to the others. What sold me is the looks, the handling, and the price. I didn't think I was looking at a Porsche or a Jag but a stylish 4 door wagon, really not even an SUV.

I really liked the car and hope next year they offer the V6 that they use in the edge and CX9 as an option.

[mikey1981]

Did you look at the window sticker?

[giddyup]

I bought my CX-7 dec 29 and drive about 5000 miles a month. The first month and a half i used 93 octane. About a month ago I switched to 87 and have been using it for the past 4000+ miles. I have had no issues except maybe a slight decrease in power. I saved $60 over the past month in gas by using 87 oct. I fill up at least every other day. As far as gas mileage i have not noticed a difference. I get 16-18 MPG regardless of the oct of fuel i use. I am going to switch back to 93 for the next few weeks and see if i notice any difference in power or MPG since the temperature is finally warming up a bit, live near Pittsburgh. I anticipate a slight power increase with no better MPG but want to give it a try since the engine should be broken in now, just hit 10,000 miles. But as far as having any problems with 87... I have had none

[Sveivo]

Hmmm...(boom08)

[kailua]

I did the same test recently and switched to 87 to see what would happen. I drove until I had a half a gallon left in the tank and then filled it up with 87. The result? Much less power (the engine was droaning all the time because it was pulling timing big time to make up for the octane deficiency) and mileage dropped. On a tankful of 91, I usually get 350 miles and still have a half a gallon left in the tank. On 87, I only got 310 miles.

To me the debate is pretty worthless. If I really was such a penny pincher to forgo the 91 octane for 87, I would have bought a Mazda3 or a Prius, etc. I like the power the CX-7 offers and with that comes the costs associated with it.

Off-topic, but I remember folks on the STI forum bitching about how there STI's were noisy and the ride quality was not good, etc. I kept thinking, what did you expect? Did you think you were buying a Lexus?

The same can be applied, here, don't expect to save tons of money and get awesome gas mileage on a turbo powered not so small or lightweight SUV.

[basunnyday]

Did you look at the window sticker?

Actual not really, the salesman printed me out the inventory sheet on the one I test drove, it had all the options and msrp.

Whats your real point? That I'm an idiot and deserve to have a car I can't put the proper gas in. That car salesmans have no responsibility to inform buyers of anything?

My original question was, " anybody using 89 octane, and what is happening?

Go find somebody else to put down.

[mikey1981]

ok, if you go back to my original post, i said, DONT TAKE THIS THE WRONG WAY. by asking if you looked at the window sticker isnt a put down.

also, YOU BOUGHT THIS CAR, its not Mazdas fault if you found out details you should have known at the point of purchase. Yes, the salesman may have never brought up the issue, but its also your responsibility as the buyer.

to say, Mazda shouldnt sell this car if there isnt a pump arond is rediculous. I think for 1. Mazda doesnt look up gas statiosn in relationship to dealers, and 2.If i make and sell ice skates, and i sell them in Florida, should it be my fault if you mistakenly buy a pair and have no where to skate given your location?

I am 100% not poking fun at you, and like i said, maybe they should have been up front and informed you, but you should have known as well.

As far as the people putting in 87 and driving and thinking its ok, it may be fine now, just hope you dont have serious problems over time with this engine, given its extreeme sensitivity to low grade gas, cold weather issues, and obviously a very big downgrade in performance. I just dont get it, to save 10+ cents a gallon . . . (im not insinuating anyone is cheap! i just dont get the big deal about 2-4 bucks a fill up)

and im not trying to get on anyones bad side, but cmon. I could see if this was a V-6, but its a turbo and it needs better fuel.

[UpNorth]

ok, if you go back to my original post, i said, DONT TAKE THIS THE WRONG WAY. by asking if you looked at the window sticker isnt a put down.

also, YOU BOUGHT THIS CAR, its not Mazdas fault if you found out details you should have known at the point of purchase. Yes, the salesman may have never brought up the issue, but its also your responsibility as the buyer.

to say, Mazda shouldnt sell this car if there isnt a pump arond is rediculous. I think for 1. Mazda doesnt look up gas statiosn in relationship to dealers, and 2.If i make and sell ice skates, and i sell them in Florida, should it be my fault if you mistakenly buy a pair and have no where to skate given your location?

I am 100% not poking fun at you, and like i said, maybe they should have been up front and informed you, but you should have known as well.

As far as the people putting in 87 and driving and thinking its ok, it may be fine now, just hope you dont have serious problems over time with this engine, given its extreeme sensitivity to low grade gas, cold weather issues, and obviously a very big downgrade in performance. I just dont get it, to save 10+ cents a gallon . . . (im not insinuating anyone is cheap! i just dont get the big deal about 2-4 bucks a fill up)

and im not trying to get on anyones bad side, but cmon. I could see if this was a V-6, but its a turbo and it needs better fuel.

I know people are not trying to pick fights, just share opinions. In that spirit, I'd like to add my perspective.

Yes we all need to be informed consumers, but I think dealers have a responsibility as well. Not all of us are car savvy enough to know, when we see that a car is turbo, that it needs at least 91. I have never owned a turbo and don't really understand how it works, all I know is that it gives me more horsepower and zoom.

I felt a bit blindsided when on my first attempt to fill up, I realized that there is no such thing as 91 in Alaska. My salesperson told me the car needed premium fuel and that was fine with me. I had never had to buy premium fuel up here before but I had seen the signs at the stations showing 3 levels of gas - one called super premium and costing more so I assumed I would be ok. After visiting every brand in town and calling some independents, all I could find was 90. Then I called my dealership to ask them if there was 91 somewhere in Alaska and they said no, just 90. I asked about the directions in the manual and they said not to worry, it will be fine.

It seems to me that at some point during the several hours that I was at the dealership the day of my purchase, that they should have told me that they were selling me a car that I had no hope of properly fueling. That to me seems like a material omission on their part. If I was taking a risk, I should have been told that and allowed to make an informed decision. Instead, they played hide the ball. To me that is not right, and not good business practice. I may have erred, but so did they.

(In Florida, there are indoor ice rinks.)

The main issue is whether the original poster can get away with 89 or if he should try to get out of the contract. It was good advice to have him ask Mazda.

[mikey1981]

hhah i know, and there are fuel pumps as well, just not near by.

[UpNorth]

hhah i know, and there are fuel pumps as well, just not near by.

Yep, I've got plenty of ice but I'd need to drive for days to find any 91 octane. (canada) has some I hear. and they have ice too. I feel gypped.

[basunnyday]

I agree with you on if premium is readily available, it is not worth the savings to use a lower grade. However some may just get along fine, depending on where they live, temperature, elevation etc.. Since octane is based on Sea level, people in Denver may get along fine on 89.

However beware when you travel the backroads of Central US, (off major interstates) you will find yourself in the situation where it is either run out of gas or use regular. All of the premium tanks have been replaced by the 10% ethenol (89 octane.) Which by the way is really rated 89.5 when it leaves the refinery, it is then up to the station to rate it 89 or 90.

What really gets me is that I live only 45 miles from one of the largest refineries in Kansas and Nebraska. I called them to see if any local distributers were hauling out the premium, trying to locate a station. They confirmed that it was not available at stations in my area at this time. However I could get some delivered with a 2,000 gal minimum order. Now all I need to do is buy me a 2,000 gallon tank. They did a nice job of giving information on octane etc.

Their current spread on the difference on the cost of regular vs 91 today was 14 cents, but can change almost daily.

[giddyup]

basunnyday,

To answer your question, yes I have been using 87 octane in my turbocharged CX-7 and I have had no problems whatsoever. When I hit the gas it gets up and goes, fast! So I do not see any problems with using 87 or 89 which is available to you. I have tried both 93 and 87 with very little noticeable power difference. They recommend 91 and you want to use 89, 2 octane points less should not be a problem as I am jumping 6 octane points and feel very little difference. I also own an 86 porsche 944 turbo so I do know a little bit about powerful cars and see no problem with the power my CX-7 is putting out by using 87. And yea, its a couple bucks a fill up but try filling up 3-4 and even sometimes 5 times a week, it adds up, quick. Last month I saved $60 by using 87 instead of 93. Is a few horsepower worth $60 a month to me? No way. I say enjoy your CX-7 with 89 octane, it really is an awesome vehicle!

[mikey1981]

do you own or lease your cx-7?

Theoretically, yea if i leased this thing, then maybe i would not care as much in terms of gas and other things, but since i own mine, i dont want a damaged engine down the road and that is worth 10+cents a gallon more everytime i fill up.

all im saying is, if down the line your car develops problems, and Mazda says its gas related (denying warranty work), u r going to own the cost of whatever that problem is. how big of a gamble is that to you? who knows, its a roll of the dice. your car may in fact be perfectly fine.

I would take a car salesmans opinion about whether its safe to use lower than 91 with a grain of salt. He wants a sale. This should be a non-dealership issue and you should take it directly to Mazda like other posters have said. And your question should not be, if i put in 89, will I be ok? It should be, WHEN i put in and use 89, because that is all thats available to me, and if this car has a problem, tell me what happens ie Warranty repair, engine repair, etc etc. I can guarantee you they will deny repair/service work as warranty work due to lower than recommended grade gasoline that MAzda says is required.

best of luck.

[Brian MP5T]

Dude, Yer gonna kill that fucking SUV on Low-Test.

It will run like shit because the ECU will dumb down the performance to offset the Shit Gas.

It will foul the O2 sensors, It will bung up the Cat-Converter.

[Platonium]

basunnyday,

To answer your question, yes I have been using 87 octane in my turbocharged CX-7 and I have had no problems whatsoever. When I hit the gas it gets up and goes, fast! So I do not see any problems with using 87 or 89 which is available to you. I have tried both 93 and 87 with very little noticeable power difference. They recommend 91 and you want to use 89, 2 octane points less should not be a problem as I am jumping 6 octane points and feel very little difference. I also own an 86 porsche 944 turbo so I do know a little bit about powerful cars and see no problem with the power my CX-7 is putting out by using 87. And yea, its a couple bucks a fill up but try filling up 3-4 and even sometimes 5 times a week, it adds up, quick. Last month I saved $60 by using 87 instead of 93. Is a few horsepower worth $60 a month to me? No way. I say enjoy your CX-7 with 89 octane, it really is an awesome vehicle!

That's like drinkin Schlitz when you could drink I don't know, insert your favorite brand of beer ___________ for pennies more. Sure, it may not kill you, but you won't feel too smooth in the morning. I bet you're getting shit gas mileage, too because the knock sensors are constantly dialing back the timing filling your combustion chambers with unburnt shit gas that passes into your cat con and will eventually foul up everything. I am also no stranger to high performace cars and turbos.
People who use premium when their car doesn't need it are foolish. People who need it and don't use it are ignorant. Not trying to be rude man, I just really disagree. (screwy)

[mikey1981]

exactly.

Now i know why i was accused by the shop foreman of using low grade gas for the reason why my engine was misfiring.

Mazda knows people are trying to cheat the engine, the dealers were put on notice across the country, and they have a punch list of "problems" for service apts made by customers claiming something is wrong with the car, when in fact its the customer using low grade gas. Mazda isn't going to service your car when you have a problem.

I had to fight for 3 weeks before Mazda would 1. authorize a warranty repair (replace the fuel pump) and 2. realize that it WAS NOT low grade gas (after i had them go fill up with shell v power 93 and my engine still misfired.) Putting in anything less than 91, if you can that is, as long as 91 or greater is avail, your just asking for a situation.

[giddyup]

You guys are saying I should be getting shit gas mileage and having engine misfires for using 87 octane? When are these problems going to start happening? I have not had any misfires and yes, I know what they feel like and I am getting exactly the same gas mileage while using 87 that I did when I was using 93. I actually had 1 tank of all highway miles that I got 23.5 MPG and that was with 87. I'm just not sure what you mean by all these problems that I should be having, cause I used 87 for almost 5000 miles and had no problems at all. I did just switch back to 93 now that my engine is broken in and am going to see if I get a big power increase and better gas mileage.

Mikey, what are these punch list of problems that would come about by using low octane fuel? Where are you getting this info from? I'm not trying to be a smartass, I would really like to know a little more on this and get some more info on all these gas issues. Thanks

And Platonium, I really dont appreciate being called ignorant. If you want to contribute some info into this matter thats fine but the next time you feel the need to insult someone I suggest you shut the f*** up!

[Brian MP5T]

^^^ Perhaps your not getting "misfires" because you don't know what it feels like to actually have the power you are supposed to have..

It could all be in the Operator Housing Reciever... Not in the motor..

[mikey1981]

My dealer. they were prepared with a troublshooting list straight from Mazda on mechanical problems due to low grade gas. They were also prepared to deny warranty service work/labor due to such issues. My car was one of many at my dealer for misfiring, bucking, detonation issues. (most of the customers however had admitted it was low grade gas in their tank, thus the foreman just assumed I was one of the many idiots)

Giddyup, refer to my ^%$%^$today thread in this same section and you can read all about it.

You may be just fine with 87, i have no problem with that as do you, all im sayin is that just beware if/when you have some major mechanical probs starting to happen. Its gonna cost you some cash. when and or if your engine misfires and maybe you are on the highway and the computer shuts your car off becuase it wants to prevent damage to your engine (happened to me twice in the same day, i almost got in a few accidents because of this) then good luck.

all these hypothetical situations we are discussing are possible reprocussions of using minimum grade octane. For the small diff in price per gallon, I would consider it more than wise to just put in the 91 and follow the rules of the game. if saving 4 bucks a week on a fill up makes you happy, then more power to ya.

[UpNorth]

I wanted to share the information I got back from Mazda on this issue. As some of you may recall, I live in Alaska and learned after my purchase that the best premium gas up here is 90. It seems to do well with the 90 and my dealership's service dept told me it would be OK when I asked them about having the CX-7 on a steady 90 diet.

With this debate, I decided to contact Mazda. Their response is pasted below. (I hope they don't mind.)
_____

Thank you for contacting Mazda.

For of all, congratulations on your recent purchase of a Mazda CX-7!

As you already know, the CX-7 will best perform when using Premium unleaded fuel with an octane rating of 91. You may use a regular unleaded fuel with an octane rating from 87 to 90, but this will slightly reduce performance, such as reduced engine output, and engine knocking. For additional assistance, please contact your local authorized Mazda dealer.

Again, thank you for contacting Mazda.

Regards,

T R.
Specialist, Customer Assistance E-Business

[mikey1981]

Had your inquiry included what if the car develops problems from the lower octane rating?

they make it sound all peachy and nice that you can use lower gas grade, the flip side of this question needs to be answered.

It was told to me through Mazda that repairs required as a result of using lower than 91 is not covered by Mazda.

[UpNorth]

Had your inquiry included what if the car develops problems from the lower octane rating?

they make it sound all peachy and nice that you can use lower gas grade, the flip side of this question needs to be answered.

It was told to me through Mazda that repairs required as a result of using lower than 91 is not covered by Mazda.

I was disspointed by the level of generality of their response as well as their brushing aside my concerns. I very specifically asked about the long term consequences of never using 91 and my concern that I would be faced with large repair bills down the road (probably after my warrantee runs out).

My fear is that my dealer telling me using 90 will be "fine" means fine for them because they're going to make some money off me later. But I'm trying to interpret things more generously and give them the benefit of the doubt. They have been just great about making things right when things don't go as intended, so hopefully they'll step up if I develop fuel related problems later.

It may be that Mazda told them 90 is ok in Alaska, because lets face it, it is cold and stays cold, at least where I live. I called the local BMW dealership about the lack of true premium gas up here and they said BMW gave them the green light to sell cars requiring 91 because of our colder climate.

I realize (though can't claim to understand) that turbos are different and have different issues, but maybe the cold is enough to make 90 ok.

In any event, my Alaska angle doesn't in any way jusitfy or excuse the rosy general response Mazda sent.

I really love driving this car and wish I could give it 91 and not have to worry about all this.

[Brian MP5T]

Octaine Additive.

[UpNorth]

Octaine Additive.

That was my next question: do those octane boosts really work and might that be a solution.

I'm taking that as a yes. Can you recommend a particular brand or any to avoid?

[Brian MP5T]

They do not replace Permium gas.

Premium also has the benifit of being a more refined product (Hence The Name)

It has less sulfer etc which are better for your engine.

That being said, the additives will prove to be expensive...

They are all quite generic except some like "NOS" are marketed with 16 year old shitbird wanna be "Brian Speilmans" who drive POS 1.6l V-Tec powered Shitmobiles with the shitty doors falling off and a shitty fart cannon epoxy glued up it's rear (If you catch my drift)

:)

Translated - Don't be fooled by hype...

[UpNorth]

Thanks for the colorful description and the rest of the info. I do buy the best gas we have in town, which is either chevron or shell, to try to capture at least some benefits of what passes for premium here.

[Brian MP5T]

Np..

[mikey1981]

LOL, well that was well said

[azcat]

Premium gas ($2.59/gallon here in KY) is cheaper than Diet Coke ($3.70 here in KY at Wally World). Are you, like, a total cheapskate, or what? Give up a pizza a month, and feed the ponies!

[Sveivo]

Premium gas ($2.59/gallon here in KY) is cheaper than Diet Coke ($3.70 here in KY at Wally World). Are you, like, a total cheapskate, or what? Give up a pizza a month, and feed the ponies!
Haha, that's some great attitude.

[Platonium]

And Platonium, I really dont appreciate being called ignorant. If you want to contribute some info into this matter thats fine but the next time you feel the need to insult someone I suggest you shut the f*** up!

I'm not here to piss people off or get into battles. If you felt I was calling YOU ignorant, than I owe you an apology. I stand by my description of using 87 octane gas in an engine where premium is required, (or at least highly recommended), is indeed ignorant.
I don't know you, so I have no right to say what I think of you, but I can have and share my opinion of your behavior on this board.

[mogulman]

I know other engines.. Subaru WRX, Audi...

They recommend 91 octane. It seems like in the CX-7 manual they Require it.

So is the sensor system in the Mazda not as advanced as other cars.

On our Subaru and on my old Audi,iIf you use 87, the engine is suppose to have sensors that can detect knock from lower grades of fuel, and reduce performance so their is no damage to the engine. It isn't supposed to hurt the engine in any way, just the performance will be reduced.

[mogulman]

From the manual... It doesn't say anything about any permanent damage from using 87 octane. It does mention it for gas with more then 10% ethanol though.

Here is the excerp from the manual:
Your Mazda will perform best with fuel listed in the table.
Fuel Octane Rating*(Anti-knock index)
Premium unleaded fuel 91 [ (R+M)/2 method] or above (96 RON or above)
* U.S. federal law requires that octane ratings be posted on gasoline station pumps.
This vehicle is designed for and requires use of premium unleaded fuel. If 91 octane fuel [
(R+M)/2 method] (96RON) is not available, gasoline as low as 87 octane [ (R+M)/2
method] (91RON) can be used temporarily for emergency purposes. Use of gasoline lower
than 91 octane [ (R+M)/2 method] (96RON) can decrease performance and deteriorate shift
quality during its use. Refueling the vehicle with the correct octane fuel a couple of times
will restore vehicle performance and shift quality.

[SuperStretch18]

I know other engines.. Subaru WRX, Audi...

They recommend 91 octane. It seems like in the CX-7 manual they Require it.

So is the sensor system in the Mazda not as advanced as other cars.

On our Subaru and on my old Audi,iIf you use 87, the engine is suppose to have sensors that can detect knock from lower grades of fuel, and reduce performance so their is no damage to the engine. It isn't supposed to hurt the engine in any way, just the performance will be reduced.

Same applies in the Mazda; the ecu detects the lower octane and switches to "emergency mode". Basically that entails a drop in performance and boost, so that there is no long term damage. The manual states this and also says that after filling with a couple of tanks of premium to purge the system, performance should return to normal.

[Killer]

If you cant afford good gas why buy a good car?

[TX Speed 6]

me and my wife took a trip to oklahoma recently for a wedding, along the way we stop at a gas station, we're running really low on gas, and have no idea where the next station would come, but all they have is 87 and 89. We fill up halfway with the 89, and hope for the best. the car on the road is fine for a while at first. then when you go to speed up to pass, not flooring it or anything, just gently giving it some gas, theres a very loud knocking sound from the engine bay, like if some dwarf was in there with a hammer, pounding away. The car feels like my turbo fell asleep, there was no power. happened every time i would start to accelerate while cruising. didn't sound like it was doing ANYTHING good for my engine. so as soon as we came to the next gas station, filled it up with premium. so thats what happend to my MS6 with low octane. hope this helps anyone thinking about using less than the recommended gas in a cx7

[TX Speed 6]

If you cant afford good gas why buy a good car?

I agree.... thats like getting a 54" hdtv and not subscribing to cable....

[papaalex]

I agree.... thats like getting a 54" hdtv and not subscribing to cable....
inspiring analogy.. (alright)

[Killer]

I agree.... thats like getting a 54" hdtv and not subscribing to cable....(werd)