Hi everyone, I am new here looking for help. My car would start up with a high rev for 5 seconds around 2400. It would then decreased to around 1200 which was still high but then it would started reving high and low like a race car ready to jump. Any help would be appreciated. I have changed the MAP sensor, coils,and the manifold. Do you think it is the Oxygen sensor (upstream)? Thanks.
error codes:
P0068 MAP/MAF
P0507 Idle air control sytem Rpm High
P0606 ECM/ Pcm processor.
After disconnected the battery for awhile only the first two codes showed.
Where is the ECM located?