I need help please!!! 2002 t4r PO171 CEL
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I need help please!!! 2002 t4r PO171 CEL
hey guys im have a bit of a problem i have a 2002 t4r with a Spectre CAI and roughly 210k (most mods are in sig) and i keep getting this reoccurring CEL its PO171 (bank 1) system too lean so i did some research and have found that cleaning your MAF sensor could fix that so i went to the autoparts store and bout myself some MAF cleaner and cleared the code then about a day later the code came back so i cleaned it again and yet again a couple days later same code. so i figured the sensor was bad so i replaced it. and sure enough the code came back a few days later and now it comes more frequently. so i had heard to hard reset my ECM so it could calibrate to the CAI. Yet again today the code came back. SO i have heard of a few possible problems, i have been told that the airflow might exceed the built in parameters in the ECM causing the system to run lean, or that i could have clogged up injectors or bad injectors. so i am done throwing parts at it (shouldn't have done it in the first place) and would like some input to see if anyone else has had this problem or any tests i can do to find out definitively what the problem is.
cheers
cheers
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Have you cleaned your air filter lately? If so how much oil did you apply to it. Remember oil should only be applied to the out side of the filter. And the excess needs to be wiped off. Too much oil from the CAI could be you problem.
Last edited by WHAHAHAJR; 01-27-2012 at 04:51 PM.
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spectre claims their filter to be an oil free filter and i just recently cleaned it with an air chuck. and correct me if im wrong but if my filter was clogged wouldn't rich not lean?
cheers
cheers
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FSM diagnostic for P0171 with a few more items than mt goat listed:
http://www.ncttora.com/fsm/1996/SIL/...e/cip0171p.pdf
http://www.ncttora.com/fsm/1996/SIL/...e/cip0171p.pdf
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so what type of test can i run to check those systems i know how to check fuel pressure, but how can i test heated o2 and engine coolant temp and such?
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The sensor #1 referred to in the FSM is the upstream sensor, the post cat sensor is #2. Both are bank #1 with these engines since they are not dual exhaust.
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update! so i ran a few tests checked fuel pressure and its sitting right at 50psi rechecked all vacuum lines no vacuum leak ran seafoam and checked ect sensor all those are in working order and still i have the code. so im about to run to the shop and see if i cant get a live scan of the o2 sensor so hopfuly we can figure it out!
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ok so another update i went to the local toyota shop told them my problem and they said that it is most likely that i got a bad maf sensor from advance auto parts and that i need a toyota MAF so i the toyota dealership and had them cross refrence the part numbers for the 2002 t4r MAF and the 2003 highlander (moms car) and they came back as the same part number so i went and switched the sensors and just my luck no code in the highlander and still got the code in my truck...(erased the code with the hand held OBD2 scanner) also yesterday i hooked up my car to the snap on modus scanner and it was showing my up stream A/F sensor was reading quite sluggish but still working. so if my upstream sensor was not working at all my car would get an O2 sensor code not a too lean code correct? because the upstrem o2 sensor tell me my fuel trim right?
please help im in desperate need!
please help im in desperate need!
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