Recently my 02 sxt started to idle rough, the car runs fine.The only problem is at a stop ata red light and the car runs at about 900rpms then it suddenly drops to like 500rpms andstartsshaking real bad. I’ve changed the plugs and wires air filter is fine. No check engine light either.

Any suggestions onwhat might be the prob or how to go about solving it?

I suspect it might be coil(althougth it looks gd), is there any way to test a coil for proper performance??

Would a 04 SRT4 coil fit in there??? Cause I could swap with mybuds to see if that’s the problem.

Thanks

 

I had the same problem its your Idle Air Control (IAC) valve it controls the rpm speed when your car is idle.

 

mine drops to about 600-650RPM and it idles so smooth, it's nice

 

Mine will drop to about 550 rpms and stays smooth.

Mat

 

its supposed to do that. perfectly normal. it may shake because you might possibly need new motor mounts. srt coil will work fine, but you dont need it.

to check for bad motor mounts, open the hood and have someoe stand on the side of the car looking in. make sure theyre on the side just in case. put the car in drive, hold the brake and give it a little gas. if the engine jerks forward or back hard then you need new mounts. do the same in reverse.

 

wat about a drop in full throttle in third it will be pushing then itll rev down a little then back up??