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p0137 - question about maf?

4529 Views 18 Replies 7 Participants Last post by  on2it
P0101 P0102 P0103 MAF sensor codes?

OK, so I got my car back friday and had no issues. Saturday rolls around, and I get a p0137 code. I try to clear it but it comes back instantly. I check under the hood and I see my intake filter wasnt secure, so the cone was laying and the pipe where the air goes (where the maf is housed) was wide open. I put the filter back on, but I still get a constant p0137 and other maf related codes.

My question is, I know its a common occurance for Evo x maf's to go bad. What is failing and causing them to go bad? Is there any sense in me getting some MAF cleaner, and trying to clean it, and see if that will fix it? Any other tricks to try?

If not, where can I get a MAF the cheapest? Also, is there any sense in taking it to my dealer, and do you think they would replace it under warranty, even though I do have a CAI?

My car now starts up and idles really low. Once its warmed up tho, drivability seems pretty normal except maybe a little less boost than usual.
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Have you cleaned the MAF? Before you do anything you should clean it first and *then* clear the code. Pick up some MAF cleaner at an auto parts store, it's always nice to have around and costs a few bucks.
Your MAF may have been damaged by debris getting in once your filter fell off.
Your MAF may have been damaged by debris getting in once your filter fell off.
Absolutely, but MAFs are expensive, so I think Kool would agree clean it first to see if it resolves the issue, if it doesn't, you'll have to get a replacement :(
OK, ill try to clean it when I get home, if not I guess i gotta buy one.

Do you think the dealer will cover one dying under warranty?
Well, it's unlikely with all your mods. Moreover if the MAF is actually bad it really isn't a warranty thing b/c it's more or less your fault since your non-stock intake fell off.
Well thanks to everyone for encouraging this thread. You're all to blame for the concoction of chocolate, coffee, ice, and shame sprayed all over the walls of my cube here in Boston. Were it not for your shenanigans, we wouldn't have arrived at the point of the OP ASKING IF HIS MAF WOULD BE COVERED UNDER WARRANTY WITH HIS AFTERMARKET INTAKE.

Upon reading said post in this thread, I nearly vomited. Thankfully enough I held back the swath of stomach acid and frappachino that made it to my stomach, however, there was no help for what was still in my mouth. Good lord I haven't had a laugh like that in a while.
well I am only guessing at a culprit, i am not saying because my intake filter fell off, that is why the maf failed, it could be a total coicidence, just something I can blame.

I mean technically speaking, we all know a CAI shouldnt cause a maf to fail, and due to the magnosan moss warranty act, they kind of have to prove the part you installed caused the problem.

So that is why I asked if it was worth having the dealer look at it.

At the same time I know mitsubishi is a terrible company when it comes to warranty work, and they will try to find any excuse to deny coverage.

My question was more to those who have had maf sensors fail in the past, and maybe they could bestow some knowlege of the processes they went through to get theirs replaced. Maybe they did get them covered under warranty, maybe not, maybe they bought their own, maybe they got it somewhere really cheap which was another one of my questions. I asked many questions, very few were answered.

I know with my extensive mods list, I ahve very little warranty left, but I would much rather have the dealer pay for something, then to take that money out of my pocket when given the choice, you feel me brah's?
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I mean technically speaking, we all know a CAI shouldnt cause a maf to fail, and due to the magnosan moss warranty act, they kind of have to prove the part you installed caused the problem.
Well actually, yes a CAI can often cause a MAF to fail. Often it can be an oiled filter that is over oiled (usually the fault of the person cleaning it). This is why I recommended you clean it first.
Well actually, yes a CAI can often cause a MAF to fail. Often it can be an oiled filter that is over oiled (usually the fault of the person cleaning it). This is why I recommended you clean it first.
AEM dry flow filter :)

but, yea i know that oil and dirt can get on it, im saying, oil and dirt wont kill it, so if after its nice and clean and it still doesnt work :)
OK, I used some MAF cleaner, and did a few rounds of sprays and cleaned it off to the point where it looked quite good.

I pulled the negative on my battery while doing it. Put the maf back in, hooked the battery back up, and had an instant check engine light.

Codes

P0101 P0102 P0103 MAF sensor codes

Sound like a bad sensor? Is there a fuse / relay for the MAF I could check too?
i thought a p0137 was a bad o2 sensor? i get that code all the time but its because of my testpipe.
OK, I used some MAF cleaner, and did a few rounds of sprays and cleaned it off to the point where it looked quite good.

I pulled the negative on my battery while doing it. Put the maf back in, hooked the battery back up, and had an instant check engine light.

Codes

P0101 P0102 P0103 MAF sensor codes

Sound like a bad sensor? Is there a fuse / relay for the MAF I could check too?
Hmm, not that I'm aware of. Got any friends with Evos? It'd be like 30 seconds to swap their maf onto your car and find out...
i thought a p0137 was a bad o2 sensor? i get that code all the time but its because of my testpipe.
your correct, i listed the wrong code lol. I pull that code all day long, it shows up in my logs, but it doesnt pop the check engine cause my tuner disabled it. Sorry, meant P0101-P0103.

just bought one on rock auto for 118 w/ a 50 dollar core charge. Figure worth a shot.

I seem to be able to drive around just fine once my car is warm, is that a safe concensus?
Looks like my new maf sensor is out for delivery for today. ordered from rock auto, fast delivery, and 50 dollar core refund, so maf was only like 70 bucks. cant hate on that.

Will update later tonight if the new maf resolves my issue :)
I used to have this issue. i have the AMS intake, which uses the oiled K&N filter. i never oiled it prior to the problems. i did some talking to other guys and this is what they suggested. buy some non-chlorinated brake cleaner. spray the maf and let dry do this 2x. make sure it is dry when you re install. i had the code come back after a few days. i cleaned it again and bought an Amsoil dry cone filter.... never had code again. from what i see some cars' maf is more sensitive than others. most people dont have issues from oiled filters. the error is usually caused by the oil from the filter building up on the sensor.
OK, I think i figured teh issue out.

So after posting the above, and being frustrated, I did what any normal man would do, and I took a road trip in the evo to KFC, to get me some chicken.

when i was sititng in the drive through I was idling at 2000 RPMS I have never had this symptom before. So i get home, and I pop the hood. I wiggle the cable that connects to the maf, and the maf itself, and as I do this I can hear my engine idle change.

so i get it to the point where the 2000 idle drops to normal. CEL still on tho. I then shut the car off. I clear the code, and then start the car up. GUESS WHAT no CEL and a perfect normal idle. I let it sit for a minute (normally I get the CEL instantly) and then i go and press on the maf/cable and boom, idle jumps and I get a CEL.

So it looks like the harness connected to the maf is not making a good connection.

OK, problem found, but now the question is how on earth do I fix this?


This is how I ended up fixing the issue. Problem is if I even touched the maf harness the wrong way, I would pull a p0102 again.

I changed my BOV last night, and afterwords had this issue happen again (prolly cause I touched the harness) so I did some more investigation.

The cable in the maf sensor harness that seemed to be causing all the trouble is the white one. If I touched that cable and only that cable with a screw driver or my finger, the idle would change.

So I pushed it in really far, and I even bent the prong on the maf slightly downward so that it touched the metal in the maf harness more securely, and so far that seemed to have remedy'd my issues.

I wonder how many Evo X owners who have maf issues, or thought their maf has failed, may have actually been having thiss issue, and this was the cause of their problem?
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^ is that fix still running ok?
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