08 model reduced engine power/general electrical issues


Asked by Jun 21, 2014 at 11:09 AM about the 2008 Pontiac Grand Prix Base

Question type: Maintenance & Repair

I've been getting the reduced engine power message for a while now randomly the car
will actually choke down and stall out when i come to a stop sometimes. It is usually
the worst when the car sits in the sun all day other times it will drive fine. I had it
scanned and it came back with P2120 and P2138 which is apparently a voltage issue
with the Accelerator Pedal Position Sensor.  I've also been having other random
electrical issues though one of the headlight connectors burnt out a few months ago
and the door locks will randomly cycle and pop the trunk when i turn the car on
sometimes, the clock and date reset randomly as well. Anyone else had these issues
im wondering if i need to replace the accelerator pedal assembly or if its another
electrical issue.

2 Answers


Sound,s to me like you have,bad ground issue,it is causing lot,s of eletrical issue,s.Before i replaced any thing,you need to find the short,it has to be a ground wire.I think you may start close to where you said head light harness burnt up.

B.C. Cornelius

my wifes car is doin same thing an wot crank sometimes

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