2004 Dodge Neon SE Misfire----Please Help

My friend has a 2004 Dodge Neon SE that I have been helping him fix. It keeps throwing a Misfire #3 code, with no other trouble codes. The basic driving symptom, at 50% throttle or more it stumbles from a stop, and misfires badly. If you apply the throttle slowly you can take the engine to 5000rpm, with out a stumble. I have checked fuel pressure, compression, and coil resistance with all within specs. Have switched wires, plugs, and injectors to see if this moved the misfire to a different cylinder, but no change was detected with the misfire code still coming up in #3. Camshaft position sensor was newly replaced 2 years ago, it had a lifetime warranty. So we swapped it out for a new one, with no effect on the problem. I am at my wits end with this so any ideas will be helpful. If you have any questions or additonal tests, I can run them and respond with the results.



Thanks

These are very sensitive to plug selection. Apparently it’s a side effect or rather inherent characteristic of the waste spark modality. I’d take the current plugs (this has GOT to be the EASIEST engine to change plugs on) and take the gap down .005 (or more for diagnostic purposes) and see if the problem takes longer to appear …or goes away all together.

Admittedly, your problem sounds more complicated. I just went through this with a 2002 Neon Se …same code. This car showed absolutely no symptoms other than the code. Ran well.

Ok. I will give it a try. I have gaped them twice now, with only very minor tweaks, but at this point I will try anything.

Ok, well I finally gave up trying to save my buddy money and put NEW plugs (with the gaps tightened up a few thou), and wires in in this car, and presto-change-o no more misfires. I believe that the Cylinder #3 misfire was a red herring, and the computer was just interpreting a general misfire to the #3 specific code. I guess the lesson learned here is when in doubt NEW plugs, not just swapped around plugs…dah. Oh well at least we figured it out. Thanks for the help.