I been chasing this problem for months now. My truck only has 56000 miles on it and I’m having random multiple misfires on all eight cylinders. Engine code P0300. I’ve replaced all spark plugs, coils, O2 sensors, cam and crank sensors, and the map sensor and I’m still having this problem. My truck starts and runs fine when it’s cold. It only misfires when the truck reaches normal operating temperature. Any advice on where to look next would be appreciated. I read need to get my truck back on the road.
My first thought while reading this was a vacuum leak. Which could be an intake gasket failure or loose hose connections at the air filter/MAF Sensor. My second thought was that a sensor failed since it only occurs once warmed. This might be a failing Engine Coolant Temperature sensor sending bad signals. Of course if there are any other codes than the P0300 they would be quite useful. Post any existing codes below in the comments. I will provide you with a list of possible causes to check.
Dodge Code P0300 Possible Causes
- (A955) ASD Relay Output Circuit
- Injector Control Circuit
- Coil Control Circuit
- Spark Plug
- Ignition Coil
- Fuel Pump Inlet Strainer Plugged
- Restricted Fuel Supply Line
- Fuel Pump Module
- Fuel Pressure Leak Down
- A Fuel Injector
- Engine Mechanical Problem
- PCM