2002 ram van, 5.2 318. The idle is irradic, it seems to pulsate. Start up is somewhat high, then will relax. When I come to a stop, and place it in park, the idle is still high as if I were still driving. This is where it will pulsate, high-low..etc. sometimes the idle will return to normal.

Any ideas?

 

Clean or replace the IAC valve.
https://dodgeforum.com/forum/dodge-r...n-the-iac.html

 

Cleaned the IAC. Seems to be running smooth now. Hopefully that did the trick.

Thanks, cheers

 

Cool.

 

Ok, cleaned the IAC. Van ran better, but still had problems. Installed new IAC, van ran better, again still seems to have a hard time locking in, so I disconnected the battery for 20 min, hooked up, drove around with ac on, and off. The van ran even better, yet it still has problems settling down and idleing right...puzzled. Any ideas?

 

Could it be the TPS sensor?

 

Could be -- cost you about $37 to find out. Sounds to me more like a vacuum problem. I would suggest you spend some time tracing the vacuum lines for trouble, and don't forget the thin hard plastic lines that connect the rubber hoses together. Sometimes those lines will develop a leak from rubbing against hard surfaces over a number of years.

 

Ok, traced the vacuum lines around and didn't see any problems. The idle seems to rev up, and be more irradic when the a/c is running.

 

That's just because the compressor puts a bit of strain on the engine at idle when it cycles on and off. When your idle is rough it is way more noticible with the A/C running. Your engine management controls may also kick idle up a few hundred RPM when the compressor is running.

 

Whoohoo, it was the TPS. Runnin smooth and right. Problem licked.
Thanks all for the help
Cheers