I reset the ECU, had a new map loaded in, and the car is still surging between 1000-1500rpms, it wont steady at all. If I tighten down the idle screw in front of the throttle body it goes to 2000rpms and stays there until I loosed slightly then right to 1000 and the surging begins again, there is no middle ground. Ive checked ground straps, disconnected the white idle control connector from the throttle body and even checked the TPS voltage which is all within spec. I am pulling a high 400 vac. and when I disconnect any vac sourcenothing changes. the Idle screw under the throttle body is all the way tight and cant go any further. Ive now tried (2) maps from (2) different cars and still nothing. The motor is a brand new street port has no miles on it, but ive run it for over an hour with no change in the surging. When I apply the throttle the car revs smooth as silk, this is begining to **** me off extremely bad.
Any advice would be appreciated, as right now im at a loss.

 

CHeck for any air leakers under tha manifold, like a misaligned gasket or sensor or something.

A small air leak can cause a surge in idle like that

I've done it before =D

 

Make sure there is a little bit of slack in the throttle cable. One of the local guys had the same problem and it turned out to be the throttle cable wasnt on correctly and had no slack at all. Just a suggestion.

 

it could be the map thats in the powerfc not matching your engine requirements
i have seen it many times before.

 

not the throttle cable ill find out about the map soon enough

 

It could be a bad idle air control motor... I see it all the time in honda's, same simptoms.

 

Ive completely disconnected the air control sensors and havent gotten any change in idle.

 

bump

 

Lube your dashpot.