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Have received some emails lately. Here is one from Charles Smith.

Title: 2003 Chrysler PT Cruiser P02302

Working on a friend's car, someone else has already changed the plugs, wires, coil and cam sensor. Misfires on cyl. 2 after warm up. But still getting a good spark from coil on 2. Turning off the key and restarting, Engine runs good again for a short time. I'm thinking the pcm has a bad quad driver and is shutting down the injector. What are your thoughts. I'm leaning towards a pcm replacement.

Actually this is a P2302 not a P02302 just to get logistics correct. P2302 is a Coil #1 Insufficient Coil Ionization code. This is a very common code with Chrysler products. The poster didn't leave a VIN or description of engine size or turbo or non-turbo. Either way these vehicles utilize a coil pack design. There is actually two coils so to speak in the one pack. Coil #1 fires cylinders #1 and #4 and Coil #2 fires cylinders #2 and #3. The PCM contains an algorithm that can infer monitored burn time of the secondary pattern to set this code.

A couple of observations. The poster states that it has a misfire on cylinder #2. Yet, the code is for Coil #1 which is cylinders #1 and #4. P2305 would be the Ionization code for Coil #2 which is cylinder #2 and #3. I have seen some cheaper aftermarket scan tools give incorrect codes and code definitions.

When the poster says "good spark". What are we talking about? How are we testing? Scope? Test plug? Adjustable gap style tester? How long it takes for his hand to stop tingling? We need some specifics here. Any late model ignition system should be able to jump a 7/8" gap with a nice white blue consistent spark. 

The poster states someone else changed various parts. Were they OE? I am a big believer in OE ignition parts especially on Chrysler products. There is a difference. I open up the hood on some of these problem vehicles I look at and it looks like the local auto parts chain store threw up into it. When I tell the shop its has a bad coil I usually get "It's new". I tell him/her new doesn't mean good.

Turning off the key and it runs well again for a short time. The PCM is taking out injector pulse when it sees a catalyst damaging misfire on that cylinder. This is perfectly NORMAL. It will discontinue operation for that key cycle. What the poster is experiencing is normal strategy. Fix the misfire and the injector pulse will continue uninterrupted.

Quad drivers is an old GM expression back in 80's when we had quad driver codes. Some Saturn vehicles used quad drivers into the 2000's. This would be a regular driver.

My recommendation to this poster is to recheck codes with a professional scan tool. Replace said replaced parts with OE parts for starters. If it still acts up then we would have scope the primary and secondary patterns. A thorough harness check. There is a very good chance that the PCM is at fault. Usually from degraded secondary ignition components. Now, if we have to go with a replacement PCM. Well, that is always an adventure with remanufactured units. Look at some of my posts. 

Charles, let me know how you make out and if I can help you out anymore.