Hey everyone,

I've done a few searches of the forum and haven't quite found anyone describing a similar symptom. After all, I've only seen one other Crossfire with more mileage than me. Therefore, I apologize if I am posting about an explained symptom and just haven't found the post yet.

As the title says, I'm just shy of 161,000 miles (and are very proud of each of those miles since it's my DD). The car is running fine with the exception of a new idling pattern when cold starting. When it cold starting, the RPM's hover around the ~1000-1200rpm range for a few seconds before dropping down to the normal ~700rpm (or so) range. However, when it drops, I've noticed it'll drop just slightly below, then rise back up to a stable idle during which the car will slightly shake. If I lightly tap the accelerator and the RPM's rise, when the revs drop back to normal, they will sink about 50-100rpms below normal idle and stabilize again at the proper range. Once the engine warms up, this symptom goes away.

I've considered doing some preventative maintenance and replacing the CPS since it's clocked so many miles, but I don't have drastic symptoms like others are getting to say this is the cause. I've also monitored after oil changes and filter cleanings and it still behaves this way. Any suggestions on things I should start checking that might cause this?

 

155k on my SRT6 and had a similar issue. Replaced the O2 sensors, plugs and coil packs and its gone. Some of the findings from my time working on the car.

1. Pug wear was excessive in the front passenger cyl with one plug tip completely burned down. Most of the other plugs were anywhere from good to poor after 75k on them. Two of the coil packs had severe corrosion on the underside traces that look like they contact the engine when screwed down. After having to replace the rear O2 due to the front cats burning up, I replaced both main O2 sensors.

2. Ensure you are keeping the oil level at the recommended level and keep it clean. I have always felt a slight drop in performance at 3500k on an oil change. the closet I get to 7k the more I notice a difference and when I check the filters they seem to have collapsed so now I swap filters at 3500 miles and oil at 7k

 

Thanks. I will check the coil packs and wires. Those are definitely old. But I changed the plugs around 100k and they were consistent and in good shape. I changed the O2 sensors a while back when the Cats were acting up. While I have everything out, I will go ahead and pull the plugs to see how they're wearing though. Keep you all posted.

 

163k update. Felt a bit of a jerk in the engine like it was about to stall when coming to a stop this morning while driving into work. The symptom would go away when I'd give it a little gas. It only happened twice though. I have yet to replace the ignition coils as I am hoping for a MIL soon, but I'm already doing research on parts that I might need to get based on symptoms others are reporting.

Does anyone know who supplied the OEM ignition coils for our cars? Was it Bosch? I'll check later when I can get under the hood, if not. If it turns out to be coil related, I'll be swapping out the CPS as preventative measures too.

 

Bosch coils. 6 of them. Things to look at are for clean contacts on the bottom of the coil that sit on the engine. When I replaced mine some were corroded and oil covered. Got mine on Amazon for around 50.00 each or you can go off brand for around 20.oo each

 

According to the tach, my car idles around 500. Have 100,000 miles, will change the plugs soon.