I've got a 2005 NA car (6-speed) with a random miss while cruising, after the engine gets warm. Runs perfect while cold, runs fine under load at about 1/2 throttle and up. I don't really notice it above roughly 2800 rpms and up. Totally random, sometimes it's worse than other times. So far I've swapped the plugs, MAF, and throttle body. Ready to swap out the fuel pump next. No CEL codes at all. Anyone else seen this?

 

Kinda sounds like a minor vacuum leak to me .....

 

Yeah maybe. I've checked all the vac hoses I can see, and it idles perfectly smooth at around 700 - 800 rpm. Hopefully I'll get the fuel pump in tonight, but I'm not real optimistic on that being the issue.

 

A fuel pressure gauge at Summit Racing cost me $36 - told me right away my pressure was fine. I"m LOVING how they built these cars with schrader valves on the fuel rail.

 

Well, I know what it's not - Replaced the MAF, throttle body, and fuel pump and filter. I guess I'll go electrical next. Crank / Cam sensors...

 

Dumb question; plug wires? With dual plugs, would a bad/weak/damaged wire not always be obvious or noticeable? (or throw a code?)

 

Yeah, maybe. I've replaced the crank and cam sensors with no improvement. I've had bad wires in the past, and they always seem worse when the weather is "wet" - There's no difference with this one. But, with that being said, I plan to swap the coil packs and wires from my SRT to this car and see what happens.

 

My Crossfire did the same. Later, it wouldn't start. I replaced the Relay Control Module with one made by Standard (about $120), which solved the problem and made the car perform much better. No code was thrown. More recently, the Crankshaft Position Sensor failed. I replaced it, and the code was eliminated. The car runs even better now. Maybe it's time to replace the camshaft position sensor just for grins.

 

Thanks for the replay, but already replaced the Crank and Cam sensors with new Bosch parts. The only thing I haven't done yet is swap out the coils / wires.

-Gary