Hey Scotty. My friend has a 2007 Chevy Impala 3.9 V6 Automatic. 174,000Miles. It used to be a Cop car and he got it this way
It shakes a bunch when its in drive or reverse
It has a flashing CEL and 2 codes
P0521 STORED (Engine Oil Pressure Sensor Performance)
P0300 Pending (Engine Misfire Detected)
The car does not make any sort of knocking.
He told me his dad changed the spark plugs, Coils, and even the fuel injectors.
here is a youtube video of the idle from the exaust. https://youtu.be/-4mYCkz2Ax8
Please help!
Flashing CEL is very serious. Don’t drive until it’s resolved. Hopefully, you can get an answer from us soon.
The 521 is common, replace the oil pressure sensor AND the pigtail (wiring harness)....
The misfires will require looking at the data....He should not have replaced parts
without proper diagnosis, now your out all that money.
For the P0300 see link below: Also test for possible blown head gasket (Scotty has a video on that).
https://carkiller.com/scottykilmer/qa/misfire-4/
Make sure you have enough oil level and the oil pressure is good. If both checks out ok, replace the sensor.
