MAF sensor throwing code?

[grcuadros]

i went into the dealer to get some warranty work done and i have a CEL on. i asked the guy to check it out and see what it was saying, i figured the o2 sensor wasnt working right because the light came on just after i changed my midpipe from stock to an MAM 2.5" catted. car runs just fine, light came on after about 30 or 40 miles after i got it changed. i jsut got off the phone with the mechanic and hes telling me the o2 sensor is just fine and the reason im getting a code is because the MAF is not used to getting so much air. he says its most likely because of the mods i have done. heres everything ive got on the car. i have 2 years til my next inspection, but it would be nice to get rid of that stuipd light.

HiBoost FMIC
AEM CAI
MBC
MAM 2.5" catted midpipe
Boost Gauge
Kartyboy SS and bushings
Greddy TT
DSM AFC

i'm only running about 8 lbs of boost. whats the deal here?

EDIT: i completely forgot to ask what the code was, but i'll get that information tomorrow if its necessary. thanks for all the help.

[dirtysouth_msp]

Find out what the code is, don't just ignore it till the next inspection, lol! Are you getting fuel cut or did you just before it threw the code?

[orng1]

you probably have a leak? intercoler piping I'd guess.

[grcuadros]

i wasnt hitting fuel cut at all. i'll give the guy a call before 6 tonite and update what he says.

[grcuadros]

just talked to the mechanic. he said the code was a P0171 which is a MAF problem. apparently i just need to put the stock airbox back on when i go to get the car inspected. does this sound right to anybody? when i had the CAI on i didnt have any CEL, it happened after i changed the mid-pipe and AFC. i'll try to change the CAI when i get home and i'll see if the light goes away. thanks.

[dirtysouth_msp]

P0171 = Bank 1 LEAN

This could be and probably is something as simple as a vac leak or a loose coupler. What is your vac reading at idle? Check all hoses and clamps (especially the coupler & clamps connecting the intake to the turbo). Also, you may want to check your wastegate actuator, the diaphram in my WGA went out and caused a vac leak, which resulted in the same code.

Most likely, the reason he is saying that it is a MAF problem is because the MAF is not reading all of the air getting into the system. Any leak after the maf could cause this code.

Also, you can clean your MAF and that may help. Pep boys or maybe Autozone sells MAF Sensor Cleaner made by a company called CRC. Just be very careful if you do this, the element is uber fragile!

[gimpo2]

is the MAF on backwards?

[speedprotegewi]

P0171 (system too lean) = clean maf sensor most commonly. we (at the lexus dealer i work at) just yank it out. look into with a flashlight and if the 2 little wires in the inside look corroded, that is your problem. bust out some generic carb cleaner and spray the shit out of it till they look clean. wait a half hour or so to make sure it is dry (wet + electricity = boom) and throw it back in. tadah no more cel :D

[dirtysouth_msp]

MSP MAFs do not have 2 little wires...(poke)

[speedprotegewi]

MSP MAFs do not have 2 little wires...(poke)

sorry my bad, i believe we have a little diode in there instead but it should be visible, just very tucked away in lots of plastic lol

[dirtysouth_msp]

Yeah, it's visible. I'm just being an ass...lol

[speedprotegewi]

no, u wanna know being an ass? the fact that we charge $190 to do that "repair" at the dealer.... 0.5 hour diagnosis 1.5 hour clean maf @ $95/hour

[dirtysouth_msp]

Bwaaaaahhhaaaaahhhaaaaahhhaaaa!

[orng1]

LOL, most dealers suck. I worked for H and it was 1hr Diag to check the codes $88.00.

[brealmp3]

i was getting the same code one time too, so i went to the part store got some intake cleaner pulled out the maf sprayed it down and let it dry. put everything back in and no more light!

[brealmp3]

and i'm quite impressed that you have all those mods and still get warranty work!

[JDM Sam]

What line is your MBC tapped off of? Your AFC settings can also trigger this code if its too lean in certain areas of the map. Vac leaks and exhaust boost leak at the manifold can cause this code too.