fuel cleaner

sm1ke

Work In Progress..
Moderator
Contributor
L
Canada
V
'18 CX-9 Signature
Cover Your Ass.
Yep. Meaning they put that in there to discourage people from adding random fuel cleaners and additives to the fuel tank and engine oil. A lot of the stuff that's out there probably won't do any harm, but every once in a while a horror story surfaces. Mazda just wants to avoid being on the hook for it.
 
tnx,so to summit the thread,
fuel cleaner-yes or no?
not trying to clean the valves because its imposible with di just keep the fuel system clean for good maintenance.
thought maybe the skyactive engines are sensitive to additives thats why mazda dont recommend using them.
tnx.
 
V
Mazda CX 5 GT-R
As others have mentioned, Mazda's blanket discouragement of adding anything to the fuel is because they have no idea what people may try and no control over the mixture.
Techron is a known effective solvent. The reason to add it about 500 miles before an oil change is just in case there is any fuel dilution to the oil.
This is regarding adding a bottle of the concentrate as opposed to using Chevron fuel with Techron which is a much lower percentage per gallon.
I look at the use of additives such as MMO and Techron as preventive maintenance. They cost maybe $25 every 10,000 miles ? Not a big gamble for me. I have never needed an expensive "fuel injector service" by a dealer due to the car not performing well, and this is from using those additives in several cars over the last 35 years and several hundred thousand miles. A scientific, controlled test ? No.
But cheap enough insurance that I will continue to do so until I observe some negative effects on my vehicle.
 

ColoradoDriver

Gen-1 Kodo Design
Contributor
L
Denver, CO
V
2014 CX-5 Touring
Quality gasolines (see: top tier) already have the detergent packs and additives you need. No need to spend more money on a fuel cleaner with questionable results.

The biggest things really are: Use top tier gas, and do longer drives where the CX-5 can actually get up to proper temp. Short drives suck.
 

Avoidin Deer

Central Virginia
Contributor
V
2019 CX-5 Reserve
Quality gasolines (see: top tier) already have the detergent packs and additives you need. No need to spend more money on a fuel cleaner with questionable results.

The biggest things really are: Use top tier gas, and do longer drives where the CX-5 can actually get up to proper temp. Short drives suck.
I'm still struggling to see the benefit of a high detergent gas in a direct inject engine. I hear from lots of sources that it's still a good idea, but I never see or hear specifics, even from some of the video gurus I respect. Since the gas does not wash against the valves, exactly what good is the detergent doing?

I agree about proper operating temps, but to me that's more for oil dilution prevention than anything else.
 
V
2010 Mazda 5 Sport
I'm still struggling to see the benefit of a high detergent gas in a direct inject engine. I hear from lots of sources that it's still a good idea, but I never see or hear specifics, even from some of the video gurus I respect. Since the gas does not wash against the valves, exactly what good is the detergent doing?

I agree about proper operating temps, but to me that's more for oil dilution prevention than anything else.
Anything in the gas won't help the valves on a DI engine. You need something injected into the air flow. Or block anything allowing carbon like stopping recirculating gases.
 

Avoidin Deer

Central Virginia
Contributor
V
2019 CX-5 Reserve
Anything in the gas won't help the valves. You need something injected into the air flow. Or block anything allowing carbon in like stopping recirculating gases.
So what value is there in a top tier (high detergent) gas in a direct inject engine?
 
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V
Soon to be 2.5T CX-5
I have never needed an expensive "fuel injector service" by a dealer due to the car not performing well, and this is from using those additives in several cars over the last 35 years and several hundred thousand miles.
No it's not. You may think so, but it's not. I've never used a bottle of the stuff, and I never will, and I've also never had to have an expensive "fuel injector service".

In fact, I know absolutely no one who has had to have that service, other than those that are gullible and mislead by their dealer or shady mechanic.

No doubt, continue to do you, though.
 
V
2010 Mazda 5 Sport
So what value is there in a top tier (high detergent) gas in a direct inject engine?
Little to None? I think Toyota injects some gas into the air stream with their DI design. I think Ford too? This is because a true DI setup becomes a time bomb.
 

sm1ke

Work In Progress..
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L
Canada
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'18 CX-9 Signature
tnx,so to summit the thread,
fuel cleaner-yes or no?
not trying to clean the valves because its imposible with di just keep the fuel system clean for good maintenance.
thought maybe the skyactive engines are sensitive to additives thats why mazda dont recommend using them.
tnx.
IMO, you can use it, but it isn't necessary if you're fueling up with any top tier fuel. I put a bottle of STP fuel injector cleaner into my gas tank and ran it to empty right before an oil change. There were no negative effects on any of the car's systems, in my experience. I'll probably do it again when the car hits 100k, just because the injector cleaner came in a 2-pack lol (shrug)

So what value is there in a top tier (high detergent) gas in a direct inject engine?
The top tier gas helps to keep the fuel system clean (most notably the fuel injectors and fuel lines). Top tier gas usually has additives that will also protect against wear, corrosion and friction.
 

ColoradoDriver

Gen-1 Kodo Design
Contributor
L
Denver, CO
V
2014 CX-5 Touring
So what value is there in a top tier (high detergent) gas in a direct inject engine?
It's a standard that you know you're getting a high quality gasoline, if nothing else.

Though I believe Consumer Reports or AAA or someone like that published a study that showed engines running top tier vs. other fuels tended to be cleaner.
 
and that-
"the Environmental Protection Agency (EPA) has required all gasoline sold in the United States since 1996 to have a minimum level of detergents to clean your system, so you're getting a fuel system cleaning already with every drop of gas that flows through your system. Top Tier gasoline and diesel fuel goes a step further. Top Tier is a standard applied to fuel that was developed by the major vehicle manufacturers to go beyond the minimum level of detergents mandated by the EPA, as well as to prohibit the use of metallic additives that can harm the emission system and fuel components. Top Tier gasoline typically contains about two to three times the amount of detergent compared to minimum EPA requirements and costs about an extra penny per gallon."
https://www.ncconsumer.org/news-articles-eg/fuel-injector-cleaner-what-does-it-do-and-is-it-really-necessary.html
 
V
Mazda CX 5 GT-R
I related in an earlier post how the use of MMO fixed a known issue with a balky fuel gauge in my 370Z. Many members on the 370Z Forum complained that their fuel gauges weren't showing the maximum level, even when filling to overflow.
Adding about 6-8 oz. of MMO to a full tank resulted in the gauge returning to normal readings by the next fill up and working correctly for the next few thousand miles, at which time another dose of MMO would fix the problem again. The MMO either had solvent or lubricating properties or both, and something in the fuel was causing the floats to get sticky after a while. About $1.50 worth of MMO would at least temporarily fix the problem.
You can either choose to use or avoid fuel additives, at least the cost over 100,000 miles isn't a major expense compared to some regular required maintenance services.
 
V
2018 CX-5 Sport
There is no need to add a fuel system cleaner if you use good fuel. I have filled my gas container hundreds of times over the years and there isn't a spec of sludge at the bottom of the can. The injectors are more likely to wear out than get clogged from dirty fuel. If you buy an older used car it might be worth adding additives because you don't know how the previous owner treated the car. About adding something before an oil change, I would think they would put an additive into the oil fill to dissolve any sludge. But again I wouldn't use any additives. It is already in the fuel.
 
V
Mazda CX 5 GT-R
I used nothing but top tier, 91 octane fuel the entire time I owned my 370Z. Mostly Arco brand. I bought the car new, drove it for 10 years and put about 85,000 miles on it. Whatever detergents and additives that the refinery added to the fuel weren't sufficient to keep the fuel gauge floats operating properly, but a few ounces of MMO added to the fuel offered a temporary fix. I did not discover that fix, but from numerous threads on the 370Z Forum discussing the balky fuel gauge readings, others mentioned adding MMO and getting positive results so I did too.
Anecdotal evidence of the efficacy of fuel additives for sure but my personal experience is enough for me.
 

Ronzuki

South Central PA
L
2018 CX5 Touring
V
w/ Pref Pkg
Too bad the solvents in Techron aren't strong enough to actually do anything.
And you know this how? By using a bottle or two and expecting miracles? Techtron is the 'detergent' Chevron puts in their gas. If I'm not mistaking, Chevron is a top-tier brand. For those of us who live in areas where so-called "Top-Tier" fuels are nearly non-existent, as I do, this absolutely works.

I've done a personal study of not using any fuel additives in my 2010 MPI Suzuki since new for many years (8) and some 80,000 miles while feeding it the widely available non-top-tier fuels in the area. After watching fuel economy and performance degrade to unacceptable levels during that time, I decided to debunk the myths. After nothing more than a bottle of Techron Complete Fuel System Cleaner per fill-up for 5 weeks straight during mid-summer, my fuel mileage alone improved 4 miles per gallon, and most notable, the throttle response improvement was very significant. Practically like it was when brand new. Weeks 6 & 7's treatments yielded nothing further in mpg gains nor ass-o-meter throttle response. Oil was changed prior to this testing and tires pressures set, driving style was the same as were the daily commutes, ambient temperatures were consistently hot and humid, and fuel purchased at the same convenient station I use normally. I check my tire pressures often, normally every few weeks when temps are stable. During this test period I checked and set pressures religiously every weekend. Now, I maintain what the 5 bottles gained for me in this car by dumping a bottle in once every 3-4 fills. Extremely cheap IMHO since I do not have top tier fuels conveniently available.

While I wouldn't expect a DI engine to have the same result due to lack of intake cleaning, good fuel system cleaners most definitely work to keep injectors clean and the fuel system's other components functioning optimally.
 
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Ronzuki

South Central PA
L
2018 CX5 Touring
V
w/ Pref Pkg
To my knowledge, modern day cleaners when used properly are no worse for CCs than improperly combusted fuel created by poorly functioning / dirty injection an intake systems or oil blow-by. Improperly combusted fuel certainly washes down the cylinders and ends up in the motor oil. Fuel is an extremely poor lubricant. Which is why I could never understand these 'extended' OCIs and extended 'range' oils (marketing). The solution to pollution is dilution. Change your oil more often if anything, not less.

As implied above, what detergents are the "top-tier" brands blending in to their fuels? As such, why I specifically chose Chevron's Techron, you know, as a precaution...just in case.
Granted, a single small 12oz. bottle treats a bit more fuel than my 2010's tank holds, but it's fairly close. It is a concentrate after all and I certainly wouldn't recommend not following dilution directions at least somewhat closely with continued usage. I have no data or knowledge of what under dilution may or may not do.

No negative effects that I can see. Efficiency is still up, throttle response is still great, passes annual state emissions testing (on winter gas), and, is purring along like a new kitten better than ever at 91,000+ miles. All I need to know about it at this point.
 

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