I have a 99 si I have headers, cam sprockets, fields vtec controller. My Idle is fluctuating. I rev it up to 2,000 rpm It will go down to 1,500 rpm and stops for a second and then idles normal @ like 800-700rpm. After I have been driving around for awhile I pull into my garage and the idle starts reving up and down constantly. I am assuming its because I don't have TYPE R cams. If any bodies knows anything pls respond.

 

What happens when you put the stock ECU back on?
If same problem check your IACV or Map sensors along with any vaccum lines that may have been bumped showing off the engine.

 

When I put my stock ecu back in my car runs fine!

 

ok.. theres your problem

 

It's a bad burn. Get a new chip.

 

I have tried 2 different programs and they both do the same thing I am trying to figure out if its because my timing is not advanced alot people have been telling me that the mugen program you should advance timing 3 degrees.

 

My friend has the same program we put he's ecu in my car did the same thing.

 

I just talked to erick of erick's racing and he said I need a fuel pressure regulator for sure.

 

hmm..I've heard of this happening on Si coupes. I believe it has somthing with the wiring on the IACV. The 2 wires that go to the IACV plug need to be swapped around and that might fix the idle problem. I haven't tried this myself though (don't have any Si coupe owning friends who run an OBD1 conversion).


[Modified by Katman, 11:42 AM 1/1/2002]