I have p0128, p0304, and p0420 engine will not run. ponti...

Q: I have p0128, p0304, and p0420 engine will not run.

asked by on July 11, 2017

I have codes p0128, p0304, and p0420,the engine will not run. when starting it seems to fire for a couple of rotations (maybe 1 second) then it just turns over. Either hot or cold. The car was on the road moving when it died. Lucky for us it died close to our house. The p0420 code has been around for a while.

My car has 172000 miles.
My car has an automatic transmission.

I believe it was the P0128 code that did it. This code indicates a faulty thermostat or a faulty coolant temperature sensor. If the P0420 code has been around for a while, this would not only not have caused the vehicle to die but would also prevent you from knowing if any other codes pop up since the check engine light would have already been on. In the event of a failed thermostat, the engine coolant is not able to circulate properly which can cause the engine to overheat. If the temperature sensor has failed as a result of this code, the gauge on the dash may not have indicated that the engine was overheating. Due to the large possibility of the engine being overheated, it is likely that one or more cylinders have low compression as a result. I would recommend having the compression tested to determine if the compression is low.

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