I've had some problems with ideling when the car is moving. The idle stops at 1500 rpm and stays there until a complete stop. Then the rpm falls to normal rpm.
I first belived it whas a foulty IAC sensor. It whas not.
Then I tried to replace the speed sensor. I've heard that could cause it. The idle whas normal a few days, then it start to act un normal again.

Now, I have no idea.

 

Check for vacuum or intake leaks first off. If you jack the throttle does it go up, drop to 1k, then go back up to 1.5k?

 

I think I have no leaks. New gaskets. I have made a video of it, and will post it soon.
If the car rolling in free gear, and I rew it high, it will come down to normal idle, with just a litle delay around 1500 rpm before it drops to 1000 rpm.
This morning with coold engine, the idle is more normal. It seems to occur when its warm.
Video will come

 

When I start it up, it rew up to 2000 rpm, and drops to 1000 rpm.

 

Could this be, because I just have a small filter on the valvecover, instead of ha hoose back to intake plenum??

 

The PCV needs to stay where its at, the breather to the intake tube doesn't matter.

Issue can be caused by timing, intake or vacuum leak, headgasket, or a sensor issue. Sensors like VSP, TPS, IAC, IAT. Also can be caused by dirty TB. These are the most common. Most my idle problems I have ever had were IAC sensor and vacuum leaks.

 

New map sensor mounted. All good

 

Good to hear. Curious as to what pointed you towards the map sensor?

 

Well, Iv had my second run to day, and it got back to the same ideling problem. Then I take a big read back and I start thinking when the hole thing started. Then I remember the idling problem whas after my dohc pcm swap. I never thought it could be the pcm. I got an egr sircuit code, I didnt have before. Could the dohc pcm read the sensors wrong? So I swapt to the sohc pcm, and the problem whas gone.
I dont know why..

 

Hmm I used dohc ecu's without this issue. Did you use the same year computer?