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Multiple eng codes and reduce eng power

M

Mr fix it

New member
Hello everyone,

i am working on a friends car for him. I can usually figure things out on most cars however I am having issues with his 2005 Grand Prix. I am getting 8 eng codes. Well really 4 that come in twice they are p2125, p1125, p0340, p2138. This is what I have noticed so far. I have fixed 5 wires that look they were cut. Cleaned the MAF sensor and retired it. The car has been stalling out while driving and the reduce eng power light is on. I have been looking for a short in the main wire bundle without seeing anything. I checked all he fuses to make sure they were good. I also found this broken and I'm not sure exactly what is is but there is a plug that goes into one side and the wires come back out the same plug....any help here will be greatly appreciated. I have been working on the car for over a week in my spare time. The picture of the item is below. The one I have no clue what it is. I am not a professional mechanic but I know my way around cars for the most part so please help in any way.
 

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p0340 cam pos sensor circuit, pcm does not detect cmp signal while engine is running, emi from coil/wires could cause poor signal condition.

p1125 accelerator pedal postion (app) system, this dtc is just telling you that the sensors are out of range or dissagreeing with each other, this will give you reduced power mode, look at the two codes under this one first

p02125 accelerator pedel position sensor 2 circuit. voltage went out of range (less then .13v or more then 4.87v) check app sensor2 signal and 5v reference for open, high resistance, short to voltage or ground, ensure there is a good ground circuit. If circuits are good suspect a failed accelerator pedel assembly or a pcm.

p2138 same as above but voltage difference between app sensor1 and sensor2 exceeds predetermined (both sensors are located in the pedel assembly)

get a better picture of that part looks like a simple relay but i cant see what that is, also where did you find that in the engine bay
 
Sea chicken,

thanks for the help so far. Sorry it has been a busy week so haven't had time to get to in depth on the car. I have figured out the part in the picture. It was the starter relay. Fixed that now it starts no problem. However, I can not get the reduce engine power to go away.

I changed the gas pedal and sensor out. I am only seeing one sensor though. I also cleaned the mass air flow sensor and the entire air intake system out. I have been looking for 4 days to find some kind of short but I'm not seeing one. I read somewhere that there was a problem with moisture getting into the connection between the instrument panel to body connector. I have looked at all the connections under the steering column and I'm not finding much. To be honest I don't know what connection I should be looking at though.

I took the driver info center out and looked behind it with not luck. There is also an after market radio installed and I was thinking that it might be wired wrong. But it seems to be wired correctly.

So the questions now are:
1. Where is the instrument to body connector?
2. How would check the current between the 2 accelerator pedals? And where is the second one? I see the one on the pedal.

I still have the engine codes with the light. Any help would be awesome. Any pictures or links would be great too. Thanks again for the help everyone. Any input is appreciated. I just want to get this car running again to its full potential.
 
Two accelerator pedal sensor as one is a fail-safe sensor. If the first one goes out, there is a backup to monitor the pedal.
 


have you checked wiring at app sensor connector, and between the throttle body connector

edit, the app connetor has 6 wires on it, 3 for each sensor,

for sensor 1
wh-bk is 5v ref
d-bu is signal
bn is low ref

sensor 2
tn is 5v ref
L-bl is signal
pu is low ref

for on the Tac module(throttle body) pins 1-3, 11-13 same colors

i dont know if this is correct for a 05, as this is for 07
 
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