Thread: Rough idle when started

I am not sure if this is where I am supposed to post this i'm new lol anyways, I have a 2000 grand prix gt with 213k some odd miles on it.... When I start it it idles really rough not sure how to explain it when first started it jumps for 700 rpms to about 900 really fast back and forth for about 5 - 10 seconds and then stops and every now and then it will randomly jump when idling and drop back down to where it about dies and than catches, also when I bought the car at 205k miles I changed plugs and wires and the crank censor and flushed trani

Mine has old msd ignition coils on it been meening to get stock ones..

Also, what type/brand of spark plugs did you install? Hopefully they were stock irridiums or some copper plugs. The ignition system in these cars does NOT like platinum plugs, not matter how much the guy at Vatozone tells you they'll be fine.

And to clean the IAC just remove it from the TB. 2 bolts IIRC. Clean the bore in the TB where it attaches, and then spray the crap out of the IAC itself. If that doesn't help then it's time for a new IAC. Usually cleaning one is just a stop-gap until you can afford/find time to install a new one.

And do NOT use anything but approved MAF cleaner for the MAF itself. If you use brake or carb cleaner it will kill it. CRC is a good brand of MAF cleaner. And just spray it clean and let it air dry. Don't use a q-tip or anything on the MAF as you can break the tiny wires inside.

I'd junk those MSD coils first, as they are known to cause issues. Then move onto the IAC if need be. Removing the coils from the equation will help in troubleshooting further.