2004 Chevy Malibu Classic 2.2 P0300 random/multiple misfire code [Archive] - Chevy Malibu Forum: Chevrolet Malibu Forums

: 2004 Chevy Malibu Classic 2.2 P0300 random/multiple misfire code

01-29-2014, 04:41 PM
I am not the most mechanically inclined person so i am hoping someone can help me here. I have a 2004 chevy malibu classic, 2.2 L ecotec. It was running fine and i parked outside of Walmart to do some shopping. it was very cold that night, but there was no issues up til this point. I went to start it after it sat for 2-3 hours and it would turn over on first crank. on second crank it turned over and was idling very rough. let it warm up and idle was still very hard. limped it home and waited til morning turned it on and still rough idle. took it in to autozone and it was running a P0300 code and a knock sensor code. I bought new knock sensor, 4 plugs, new wires and replaced it all. Plugs were gaped much to far, almost double the guy told me, and the were pretty burnt up. I replaced knock sensor and 4 plugs and wires. Car still idling very rough at this point. the knock sensor code cleared but still running a p0300. replaced the coil pack and still running the p0300. rough idle, no acceleration, shifting at very high RPMS, and down shifts to 3rd and gets to 3-3.5K rpms up hills, the engine takes forever to heat up, and the oil temp gauge will drop if idling at light with the heat on, drinking gas at an unbelievable amount for the car. there is a very strong fuel smell in the exhaust. where do i go from here? Ignition module? that is my next step i think, because its getting fuel fine, and i took the plugs back out and seem to have even amounts of wear on them. any input would be greatly appreciate. Thank you!

01-30-2014, 04:53 AM
Check your fuel pressure regulator.

I had an '87 Ford Ranger and the FPR went bad. I went from 23 to 10 MPG with black smoke. Replaced the FPR and it solved it.

Not saying that's what yours is, but check it to be sure.