Hi my new rebuildt s5 t2 engine idle's on 2500-3000rpm from startup cold, and will not idle lower when its get hot eighter...
somebody that have had the same problem before?
would be nice to get a normal idle 😉

 

You can control idle rpm with the screw on the BAC valve on FC Turbo engine! But before this you should "jumper" the green connector. Jumping the connector "tells" the ECU to enable the idle control when you rotate the BAC valve screw. Without jumping the connector rotating the screw on the BAC valve il useless.

Also i had a similar problem to yours......but the BAC valve screw was not guilty.

When i worked on the engine i slighty bent the support of the CRUISE CONTROL cable. So when i started the engine it always idled at 2500/3000.

Check che CRUISE CONTROL CABLE and check if the support of the cable is bent so the cable is tight and not in the rest position.

Here is the thread with the bent cruise control support photos. Hope it helps!
https://www.rx7club.com/2nd-generati...conds-1127191/

 

The wire for trottle and cruise are not the problem..But maybe i should check out the bac 🤔 I think i will try to calibrate the tps also, and maybe try to adjust on the screws there...
could be a lot things, so must go true the list 😉