I bought a 2005 Chrysler 300C with the 5.7L with 192k miles as a small project car.

Upon purchasing the car, I knew that it had a bogging and stalling problem. I was also aware that the car was throwing O2 sensor codes (P0031, 37, 51, and 57). Right upon being it home, I noticed that the spark plug wires were placed in the wrong order. I put the plugs in the correct order, then the car stopped bogging and stalling.

After this, it was idling so smooth for a long time that I felt confident enough to take it out on the road. The car was idling for about 20 minutes, and I was able to drive it for another 20. I brought it home that night thinking a basic tune up will make it close to perfect.

The next day, I went to start the car and it started idling very rough, and died on me. It spat out some white smoke when revving lightly. It was throwing a Cylinder 1 misfire code, and a Multiple Cylinder misfire code. I checked all the plugs and noticed that the first spark plug in cylinder 1 had no gap. I replaced all the plugs with Champion Copper 570 (and I did double-check to make sure they were gapped properly). This ended up getting rid of the misfire codes, but it still runs very rough. (Coils seem relatively new, and the wires seem good).

My wife’s uncle, a mechanic, came by to see what’s going on. He drove it around the neighborhood and could definitely feel the misfiring but also felt that the throttle position was off. He performed a throttle re-learn. After this happened, the car acted normally for 10 seconds then went back to its rough ways. We pulled it back into the garage and it would not turn over. The car was at operating temps at this point. We could not get the car started again, it continuously cranked. He said I should wait until morning when the car was cold to see if it’ll start then. I did that, and it did start, but wouldn’t stay running for long.

Here’s the weird part. Since then, I only changed the camshaft position sensor. I was going to do the crank position sensor later. The car now starts and idles rough, but not as rough as before. It’ll idle for a long time with no problems. Still no misfire codes, except now there’s a P0113 code. It still isn’t drivable.

All in all, I’m really unsure as to what I should try next. I’ve heard that replacing those two sensors may fix it, replacing the throttle body, etc. I was thinking about the PCM needing to be replaced but my wife’s uncle said that it reacted to the throttle re-learn and does not think the PCM is the problem. When I next see him, we’re going to take the valve covers off and see what’s going on under there.

Any other suggestions, or ideas as to what could be going on?