I just had some engine work done. Hotcam/PPd Heads/Headers. I have PCMforless chip.
My car is a 93 M6.
The car had no driveability problems prior to the work.
Here is what she is doing.
When we 1st started it up she idled @ 1000rpm then when she warmed up she idled @ 800rpm then every 5 to 8 secs the idle would drop to 400rpm or so then go back to 800rpm or so.
Cleaned the idle control motor pintle, put new gaskets and put it back together along with new plug wires. Seemed to be fine but then again 800rpm then stumble to 400rpm. No service light coming on.
Drove it around the block a couple of times parked it came back 15 minutes later and she was hard to start, idling now @ 1500 to 2000rpm. I checked for obvious intake leaks but can't find any.
Beside the above work the only other thing changed is the elimination of the AIR PUMP. I had the connections blocked off.
Any ideas on what I should look for?

 

You may want to have your programming checked.

 

I dont think anything mechanically is wrong with the car. The surging from 400-800 rpm in closed loop is the car searching for a good air/fuel ratio. Basically all your problem are in the tune you received. You might wanna find somebody in your area to tune your car . I know pcm4less does good work but sometimes these things just happen.

 

you may want to check out norris motorsports in orlando as they do good work. Or A place here in jacksonville called North side Dyno tunes does tunign on lt1 cars as well.