Turbodude06

I just bought this 96 GT auto for my wife... When we got the car it was throwing a cel for P1131f which I thought was a bad 02 sensor... So I went and bought those mil eliminators... Ever since I put those on the car, it has been throwing cel codes for P0136, P0156(It threw this one once before the mil eliminators too), and the P1131f... So yesterday I cleaned the MAF with some electrically safe cleaning spray, that I read could be the problem, but it didn't do anything at all... I'm hoping that someone on here could help me out with this problem....


P.S.- Mods are a cold air intake, BBK x-pipe, and flowmaster exhaust.....

Turbodude06

Oh and when its in overdrive/4th the torque conv. seems to not want to lock or what ever it kind of slips. I read that, thats because of the MAF not fuctioning properly. I keep looking up P1131 code and I'm getting so many different answers...

Turbodude06

Does anyone have any idea's at least??? I need this gone so I can pass emissions...

nehila50

1131 is for bank 1 front o2 sensor, MIL eliminators are to be put on the rear o2s to fool the computer if you dont have catalytic convertors, did you put them on the rears? 136 and 156 are for rear o2s. Here is a pinpoint test for the 1131

H40 DTCs P1131, P1151, P1132 AND P1152: UPSTREAM HO2S(S) NOT SWITCHING. DTCs P1130 AND P1150: FUEL SYSTEM NOT SWITCHING AT THE ADAPTIVE LIMITS (RICH OR LEAN)
Diagnostic Trouble Codes (DTCs) P1131 bank (1) (Cylinder #1) and P1151 bank (2) indicate the fuel/air ratio is correcting rich for an overly lean condition. The HO2S voltage is less than 0.45 volt. DTCs P1132 bank (1) (Cylinder #1) and P1152 bank (2) indicate the fuel/air ratio is correcting lean for an overly rich condition. The HO2S voltage is greater than 0.45 volt.

DTCs P1130 and P1150 indicate the fuel control system has reached maximum compensation for a lean or rich condition and the HO2S is not switching.

DTC/HO2S Reference List

HO2S-11 = DTCs P1131, P1132 and P1130
HO2S-21 = DTCs P1151, P1152 and P1150
Possible causes:

Fuel system

Excessive fuel pressure.
Leaking fuel injector(s).
Leaking fuel pressure regulator.
Low fuel pressure.
Contaminated injector(s)
Induction system

Air leaks after the MAF.
Vacuum leaks.
Restricted air inlet.
PCV system.
Fuel purge system.
Improperly seated dip stick.
EGR

Leaking gasket.
Stuck open EGR valve.
Leaking diaphragm.
Base engine

Oil overfill.
Cam timing.
Cylinder compression.
Exhaust leaks before or near the HO2Ss.
Check air intake for leaks, obstructions and damage.
Check air filter, air filter housing for blockage.
Verify integrity of the PCV system.
Check for vacuum leaks.


here is the pinpoint test

H80 DTCS P0136 AND P0156 MONITOR DOWNSTREAM HO2S OUTPUT VOLTAGE FOR ACTIVITY. DTCS P1137, P1138, P1157 AND/OR P1158 INDICATE LACK OF HO2S SWITCHING
DTC P0136 and P0156 indicate the output voltage of the downstream HO2S is less than some calibratable functional window. KOER DTCs P1137, P1138, P1157 and P1158 can only be retrieved during KOER Self-Test when the fuel control is ramped rich and lean and monitored for a voltage change on the downstream HO2S.

Possible causes:

Wiring Concerns
Pinched, shorted, and corroded wiring and pins
Crossed sensor wires
Other Concerns
Exhaust leaks
Contaminated or damaged sensor
Are any of the above concerns present?
Yes No
SERVICE as necessary. COMPLETE PCM reset to clear DTCs (REFER to Section 2A, Powertrain Control Module (PCM) Reset ). RERUN Quick Test. Continuous Memory DTCs P0136 and P0156. GO to H81 . All others GO to H82 .

Turbodude06

WOW! Thats a lot of info and a lot of things that could be wrong .... But yes I put the mil eliminators on the rears.... Can I put them on the fronts to get ride of the codes or will the rears just read it then?????

nehila50

the mil eliminators need to stay on the rear, the pcm needs to see voltage switching on the front two, mil eliminators keep the voltage steady for the rears. Have you done anything to the car recently that might be causing your problems? Any exhaust leaks or have you removed any parts lately?

Turbodude06

no i just bought the car and the next day it threw these codes so i figured they just reset them before i got the car. im thinking MAF cause i dont think the cleaning it helped but im just not sure...