Fuel System for Bank 1 too lean. What could it be?

[DougMd]

The check engine light came on, and I took it to AutoZone where they ran the diagnostic. Could someone please let me know what possibilities could be causing this? I'm sure it could be several, or even many things, but some possibilities would be greatly appreciated!

Thanks!

[Witchdoktor]

http://www.msprotege.com/forum/showthread.php?t=123616637&highlight=bank+lean

P0171?

[Witchdoktor]

and what model? FYI - the 1.6 mass air flow sensor is under an extended warranty

[DougMd]

I have the 2000, 4 cylinder, 1.8 L Protege with about 50k miles on it. I just checked the air filter, and there is a crack about 2 inches wide, 1/8 inch wide on the top side of the filter that surely is allowing in more air.

Do you suppose that is what it could be? I will replace that soon.

Thanks for the reply post!

Darn shame what happened to PT. He is an absolute hero in my book! I was so sick about what happened, I had to turn off the OLN feature's part where he was killed.

[Shane5425]

u need to replace the first o2 sensor, or a possible maf, but on the 1.8 its prolly the o2 sensor.. on the 1.6l though its the maf.. check ur maff since u say ur filter is busted.. might have gotten the maf dirty..

[Rio Racer]

Dunno about mazdas but in tiburon that code is caused by a dirty MAF or getting oil on the MAF from over oiling your cone filter. It's remedied by cleaning the maf with a cotton swab soaked in alcohol or spraying it with CRC electronics cleaner.

[zerocover]

I have the 2000, 4 cylinder, 1.8 L Protege with about 50k miles on it. I just checked the air filter, and there is a crack about 2 inches wide, 1/8 inch wide on the top side of the filter that surely is allowing in more air.

Do you suppose that is what it could be? I will replace that soon.

Thanks for the reply post!

Darn shame what happened to PT. He is an absolute hero in my book! I was so sick about what happened, I had to turn off the OLN feature's part where he was killed.

Yes its the air filter.
The code means running lean. Too much air. This can be caused by a bad maf but having a crack somewhere will also let in more air. The air would need to come in from after the maf though. OR really close to it.

[DougMd]

OK guys. First I am going to replace the air filter, and if that doesn't work, clean the "maff" Mass Air Flow sensor? At first I thought the cracks in the filter let in a lot more air, but there is still filter beneath the cracks, telling me it is really minimal when you consider how big the filter is. But I will change it and see.

You guys have been great. Thanks!

[Witchdoktor]

OK guys. First I am going to replace the air filter, and if that doesn't work, clean the "maff" Mass Air Flow sensor?

yes. maf = mass air flow sensor.

notice any difference in performance or mpg ?

[DougMd]

We haven't noticed any difference at all in performance, and I don't believe any in MPG either. I'm going to get an air filter now...

[Kansei]

You may need to reset the ECU to clear the check engine light. IF you haven't done it before just disconnect the battery for a few minutes. If you have the factory alarm be warned though. When you reconnect the battery, it will instantly be armed so you'll probably set it off if you don't have the remote nearby to unarm it.

[DougMd]

Well, I changed the air filter, unhooked the negative terminal for 10 minutes, and put it back on. I ran it a few minutes, and the light didn't come on. Then my wife took it to the store about a mile away, then back and it still didn't come back on. Does this mean it is probably fixed, or would the CEL take more time to come back on?

Thanks very much for all the great advice!

[Kansei]

Well, I changed the air filter, unhooked the negative terminal for 10 minutes, and put it back on. I ran it a few minutes, and the light didn't come on. Then my wife took it to the store about a mile away, then back and it still didn't come back on. Does this mean it is probably fixed, or would the CEL take more time to come back on?

Thanks very much for all the great advice!

If you've driven it a few times then it probably isn't coming back. I know when I installed my new ECU my CEL for my missing 2nd oxygen sensor didn't come back on for maybe 15 minutes or so. I had the car just sitting in the garage running for a while until it warmed up, then took it out for a little drive. The next time I started it up the light was back on.

[Shane5425]

car has to see the problem 2ce .. once per key cycle.. give it about a day.. or 2 you should be good..

[DougMd]

OK, thank you. I see that the maff is above the air filter, two phillips head screws as someone advised. Cleaning it will be the next thing I do if the CEL comes back on.

[DougMd]

Well, the light came back on, and I unscrewed the maff, but it gives resistance when I tried to pull it out. Should I force it, or do I need to go into that plastic black box it goes into and unhook something?

[orphman]

u need to replace the first o2 sensor, or a possible maf, but on the 1.8 its prolly the o2 sensor.. on the 1.6l though its the maf.. check ur maff since u say ur filter is busted.. might have gotten the maf dirty..

bingo we have a winner!

[DougMd]

I'm trying, but it is hard to pull out. Do I force it out, or is there something else I need to disconnect/unsrew other than the two phillips screws? I took off the wire connector, and will need pliers to grip it just to pull it out if that's what I should do.

Thanks!

[orphman]

I'm trying, but it is hard to pull out. Do I force it out, or is there something else I need to disconnect/unsrew other than the two phillips screws? I took off the wire connector, and will need pliers to grip it just to pull it out if that's what I should do.

Thanks!


yank away!.. not sure to be honest.. never done on car in question

[DougMd]

Well, I pulled the entire air assembly off and tried to clean the filament (piece that is in the center of the air assembly), but 80% of the filament broke off when I rubbed it with an alcohol-dipped cotton swab! I put everything back together, unhooked the battery and a half hour later hooked up the battery to see how it would run. It cut out on me twice before I could get it into gear and drive it, but when I got going, it ran fine around the block. The CEL went on again right away, and I wonder if it cut out because it was raining some when I had the hood open (something got wet), and NOT because I broke off the filament?

Any ideas on what to expect, since I screwed it up? The plug from the outside does not lead all the way in the middle of the air element, and the filament wasn't directly connected to it...

I know I gotta do whatever is necessary, at least before the emissions inspection. At least I tried. Now I just want to be sure the darn thing runs ok in the meantime!

[Kansei]

o_O

you broke ze filament on the MAF? That can't be good at all. See if someone on here is selling one, I seem to remember someone buying a wrecked P5 to part out.

[DougMd]

Yes I did, if it was the thin strip that sticks into where the air goes! (omg)

Can that be put on separate, or do you have to get the entire air assembly?

[Witchdoktor]

I'd get another one from the junkyard

[DougMd]

The whole big assembly or can I get the little filament separate and just install that?

[Witchdoktor]

the whole assembly. should be arond 40 bucks from a junkyard

[Kansei]

The whole big assembly or can I get the little filament separate and just install that?

I wouldn't really call it big, but just that little cylinder with the box on it and the plug on the side. Search on here to see if someone is selling one or just check a junkyard.

Can anyone confirm if there is a difference or not between the 1.6 and 2.0 MAFs?

[DougMd]

Thanks! You've been a big help to me in this forum. Maybe I should stick around the junk yard and see if the light goes out, or if I have to go back in and get an oxygen sensor too!

[Witchdoktor]

the light will go out when you reset the cel, they won't come back until a couple of drive cycles (assuming you didn't fix the cel) so if you can get a good deal on the primary O2 sensor by all means grab one. only thing I'd stay away from are parts with a ton of miles on them.

[DougMd]

Right, it isn' very big, but is the top of the air filter with the box on top, plugs and hose off the side. Mine is the 1.8 L, in case that makes a difference.

If anyone in here has one for sale, let me know. The only junkyard I know of is 34 miles away and they say they doubt it but MIGHT have one in the yard, but it is raining hard and not worth it for me to go right now.

Funny, the car cuts out once after starting it each of the 5 or so times we've started it since I broke off the sensor (just to be sure, I broke the little fragile rectangular chip looking sensor thing sticking into the air tube). But after cutting out once, it seems to ride fine upon restarting it. So far anyway...

[Kansei]

Right, it isn' very big, but is the top of the air filter with the box on top, plugs and hose off the side. Mine is the 1.8 L, in case that makes a difference.

If anyone in here has one for sale, let me know. The only junkyard I know of is 34 miles away and they say they doubt it but MIGHT have one in the yard, but it is raining hard and not worth it for me to go right now.

Funny, the car cuts out once after starting it each of the 5 or so times we've started it since I broke off the sensor (just to be sure, I broke the little fragile rectangular chip looking sensor thing sticking into the air tube). But after cutting out once, it seems to ride fine upon restarting it. So far anyway...

If it's running the sensor must be getting some sort of reading, because if you just unplug it the car will start up and just stall out (I've forgotten to plug it back in a few times).

I bet your air/fuel ratio is way off though, I'd be careful.

Oh and on the 1.8, I think a lot of things between the 1.8 and 2.0 are the same if I remember correctly. Good luck with everything. If the junkyard near you doesn't have anything, you can always check out mazdarecycling.com and if you want it new either call the parts department at Mazdastuff.com, which is a dealership in Texas that has amazing prices for OEM parts, or PM ken from protegegarage.com, as he can also get OEM parts at a good price. I use mazdastuff for getting oil filters and such.

I'll look around in the for sale section on here if I can find the thread where someone definitely had the 2.0 MAF for sale.

[Kansei]

*ding ding ding*!

found it

http://www.msprotege.com/forum/showthread.php?t=123629753&highlight=maf

[DougMd]

You guys have been great! Thanks for all the help.

The autozone near me said it would run $178 plus $45 "core charge." I'm not positive it is the part I need but explained it as best I could.

Do you know of any particular NAME for that assembly?

[DougMd]

I realize the generation of my Protege (2000) goes through 2003, right? I see another for sale that looks exactly like mine, but doesn't specify that it will work with my 1.8L. Are there different maffs for the 1.6L, 1.8L and 2.0?

[Kansei]

I realize the generation of my Protege (2000) goes through 2003, right? I see another for sale that looks exactly like mine, but doesn't specify that it will work with my 1.8L. Are there different maffs for the 1.6L, 1.8L and 2.0?

I think the 1.6 has a different mass airflow sensor, but I think the 1.8 and 2.0 might be the same. I'm sure someone else on here with a 1.8 would know a lot more than I do though.

That's not a terrible price (probably better than from a dealership) but that guy on the forums has one for 50 if you find out that it'll work with the 1.8

Oh and the name of the assembly is just "mass airflow sensor" or "MAF"

[DougMd]

I just talked to a guy in the parts section of a dealer. He told me the sensors are different on 1.6, 1.8 AND 2.0. He said the 1.6 looks different from the other two. Though the 1.8 and 2.0 maff look the same, the sensor itself is different. I do NOT have the wagon (P5), and don't know if that makes a difference either. Clueless me just found out about that distinction too and didn't think to ask him.

[Kansei]

I just talked to a guy in the parts section of a dealer. He told me the sensors are different on 1.6, 1.8 AND 2.0. He said the 1.6 looks different from the other two. Though the 1.8 and 2.0 maff look the same, the sensor itself is different. I do NOT have the wagon (P5), and don't know if that makes a difference either. Clueless me just found out about that distinction too and didn't think to ask him.

Being wagon doesn't make a difference at all. all the 2.0s have the same parts.

1.6L: ZL01-13-215R-00
1.8L: FP39-13-215R-00
2.0L: FS1E-13-215R-00

Those are the part numbers for the MAF. Did he say how much the sensor would be from the dealer? Depending on how high of a price it is from the dealership Mazdastuff.com or Protegegarage.com may be able to get it to you for close to or better than the price you got from Autozone.

[DougMd]

Yeah, he said it would be around $319 or something like that. I figure I can get a better deal elsewhere. What's odd is that wherever I've seen used ones for sale, the seller does not distinguish between the 1.8 or 2.0 so I have to ask and get a reply before considering to buy it.

[Kansei]

Yeah, he said it would be around $319 or something like that. I figure I can get a better deal elsewhere. What's odd is that wherever I've seen used ones for sale, the seller does not distinguish between the 1.8 or 2.0 so I have to ask and get a reply before considering to buy it.

If they post a picture of it, it'll say FS1E I think right on top of the square piece if it's for the 2.0. What sucks is that about 75% of the Proteges on this forum are the 2.0, and then it's like 20% or so 1.6s and the rest is the 1.8. Its by far the rarest of the third gen Proteges.

[DougMd]

Dod Gammit! Well, I called the recycling.com and they want $125 for a used 1.8L, 6 mo. warranty. Much better than $319 but not $40 or $50 either. I'm in no real big hurry... unless it stops running!

[Kansei]

That's not that bad, sucks that you happen to have the rarest protege engine :(

[DougMd]

Well,

I can get one for $125, used with 6 mo. guarantee or $180 new. Zverg, which would you get? By the way, the car kept cutting out on me this morning, which may have been contributed by the cold. Had to take my truck in to work. No big deal, but I hope to order one by COB today.

Oh, and the one I looked at on ebay, it is the 2.0 and expires in a few hours. I could get it for WAY cheaper, but don't know how it would work in my 1.8.

[Kansei]

I wouldn't risk the 2.0 MAF, as it may be tuned differently and cause your air/fuel ratio to be off.

I would go with the used one since it has a guarantee as long as it is off a low mileage car.

[DougMd]

There's no telling if it is or not. I suppose if it is cleaned, I should be ok for quite some time, right? BTW, I have about 50,000 on the car, so figure on having it another 4 to 6 years at least.

[Kansei]

I don't know if a MAF is something that really wears out, so as far as I know you should be ok as long as it is in good condition.

How long is the warantee on the one that is new?

[DougMd]

Well, the new one at AutoZone is 3 month warranty, and the other one is 6 months, so I went with the $125 recycled one with the 6 months and it is due to arrive in 5 business days.

He said it didn't come with the assembly with the black box, etc. but that there are four bolts and they are easy to get to in order to swap it out. I emphasized 1.8 Litre Mass Air Flow Sensor and he said that is what he is referring to as well, and it looks to be the same as Miata so if the box says Miata, don't freak out.

Does all this sound right? I can't thank you enough for all the advice and assistance!

[Witchdoktor]

the maf for my 1.6 is a one piece assembly everytime I got a replacement. you car stalling out in the cold is not normal. when u do replace the maf, disconnect the battery for a few minutes to reset the ecu. some even say to hold the brake pedal down for 30 seconds while the battery is disconnected. good luck and keep us posted.

edit - my maf does not say miata, if it's the wrong part get a refund and go with autozone or contact Captain KRM P5 (ken) @ protege garage

[DougMd]

OK. It stalls out because when I tried to clean the maff with an ear swab and alcohol, idiot me broke off about 80% of the fragile sensor. When warm, it starts, cuts out, then starts and runs ok. While cold this morning, it cut out on my after about 5 starting attempts so I took my truck in to work.

At least I'm learning a thing or two thanks to you guys in the forum...

I did ask about the price and got an email from a ken miller at mazda3online or something like that and he wanted $180. I don't know if this is the same ken you were referring to or not.

[DougMd]

By the way, if the maff isn't the problem my CEL went on, it is the first oxygen sensor. That is the one underneath the front of the car that is easy to get to, right? As I look underneath with my head beneath the license plate, I see what appears to be an oxygen sensor down there on the pipe just as it comes out to run back to the muffler.

[Witchdoktor]

By the way, if the maff isn't the problem my CEL went on, it is the first oxygen sensor. That is the one underneath the front of the car that is easy to get to, right?

yep, the O2 sensor is in the heatshield. change the maf asap dude

[Kansei]

By the way, if the maff isn't the problem my CEL went on, it is the first oxygen sensor. That is the one underneath the front of the car that is easy to get to, right? As I look underneath with my head beneath the license plate, I see what appears to be an oxygen sensor down there on the pipe just as it comes out to run back to the muffler.

Well I'm glad you found out what was causing your problem. The first oxygen sensor isn't that one you are looking at, it's higher up. Pop the hood, and it's the one right there as the exhaust manifold comes out of the block.

[DougMd]

I didn't necessarily find out what is causing the problem. I just went off of what feedback I got from guys responding to this post, that with the 1.8L it probably isn't the maff but the first oxygen sensor.

The maff is due in around Monday next week. I HOPE he is sending the right thing and it won't be hard to put it on!!!!!!

[DougMd]

Update:

I got the maff and put it on last night, and it seems to be running fine like it was even when the CEL was on before I busted the sensor. I haven't driven it long enough to see if the CEL comes back on though, and suspect it will if that is the likely culprit in the 1.8L. If it does come back on, I guess I should change the oxygen sensor next.

Thanks for the heads up on the sensor location. Is it easy to hook up the much cheaper universal oxygen sensor?

[Kansei]

Thanks for the heads up on the sensor location. Is it easy to hook up the much cheaper universal oxygen sensor?

If you are comfortable crimping 3 wires, yeah. I just bought one from oxygensensors.com myself, it was like 59.99 for the sensor and 9.99 for the oxygen sensor socket.

[DougMd]

When you say "crimp," you mean stripping the plastic casing and twisting the three wires together with a wire nut or something? Pardon my complete lack of experience! I have no problem doing something fairly simple that requires no special tools other than the sensor wrench, but if it requires more sophistication I might not opt for the universal.

[Kansei]

When you say "crimp," you mean stripping the plastic casing and twisting the three wires together with a wire nut or something? Pardon my complete lack of experience! I have no problem doing something fairly simple that requires no special tools other than the sensor wrench, but if it requires more sophistication I might not opt for the universal.

It really isn't too difficult. You just get some crimp connectors (butt style) like these http://www.radioshack.com/product/index.jsp?productId=2151268&cp=2032058.2032231.2032283&parentPage=family or something similar. You strip each wire on both sides, and one by one stick a stripped wire into the connector and then use a crimp tool (like this: http://www.radioshack.com/sm-kronus-4-way-crimping-tool--pi-2062789.html) to lock the connector down around the wire. Do the same with the wire on the other side of the connector and crimp it down. It's a very simple process and is decently durable. Just slap some electrical tape to seal crap out (high temp electrical tape if they make that) and you should be set.

I'm sure someone on the forums who lives close to you would gladly help you out to save you the huge price jump that going to a non-universal is).

[DougMd]

Thanks!

I may try to take that on, if my CEL comes on again.

[Kansei]

Thanks!

I may try to take that on, if my CEL comes on again.

If it will be coming back on it should come on by the time you start the car a few times and drive it.

[DougMd]

Well,

The light DID come back on. Oh well, I guess I will swap out the O2 sensor at some point.

Question:
If it takes a few hours of driving for the light to come back on when the oxygen sensor is bad, what if you take a car to emissions just after clearing the computer by unplugging the battery for 10 minutes or so? Will the car pass since the CEL isn't on yet? Nowadays they only plug the diagnostic in the computer and don't run the treadmill...

[DougMd]

KanzeiZM,

I sent you an email. I found this sensor and it already has connectors and everything, so I should only have to hook it up with no crimping/splicing. Does this look like what I need for bank 1, which is the oxygen sensor located on the exhaust manifold accessible from the hood and NOT the second one located beneath the car?

http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=8046681387

[Kansei]

Well,

The light DID come back on. Oh well, I guess I will swap out the O2 sensor at some point.

Question:
If it takes a few hours of driving for the light to come back on when the oxygen sensor is bad, what if you take a car to emissions just after clearing the computer by unplugging the battery for 10 minutes or so? Will the car pass since the CEL isn't on yet? Nowadays they only plug the diagnostic in the computer and don't run the treadmill...

Yes, in terms of emissions testing you should be ok as long as the CEL isn't on.

Oh and I responded to your e-mail. I think that oxygen sensor will be fine as long as it's a 4-wire.

[DougMd]

OK thanks. I ordered it and will pick up a socket at a local auto parts store.

[DougMd]

The saga continues...

[DougMd]

I got the oxygen sensor in the mail, and put it on using a color chart from Bosch, even though the one I got wasn't Bosch. I guess I'll find out if it works within the next few days!

[Witchdoktor]

Question:
If it takes a few hours of driving for the light to come back on when the oxygen sensor is bad, what if you take a car to emissions just after clearing the computer by unplugging the battery for 10 minutes or so? Will the car pass since the CEL isn't on yet?
I tried that once but the scanner picked up the fact the car didn't have enough drive cycles.

how does the car run, any hesitation?