I recently finished my B17 swap into my 93 hatch. Ever since it was done I have had a small idle issue. It seems worse some days, better on others. The throttle body is a first gen 58mm B16 with firewall mounted map. The TPS has been removed by the seller and was on there with one bolt. The voltage was .3 at idle and 3.5 at full throttle. I adjusted it to .45 at idle and 4.55 at full throttle. That didn't seem to do anything for the idle issue. When you first start the car up, the idle speed shoots to 2,000rpms, then drops down to 800rpms or so. This is when its hot. When cold, it will hold the fast idle around 2,000rpms and then slowly comes down. It will also fluctuate when cold bouncing around 200-500rpms. You can hear a slight miss in the exhaust as well. I am still using the stock throttle cable with a modified bracket so it fits correctly. If you blip the throttle then sometimes it "sticks" at 2,000rpms... Another blip will usually get it to drop down around 800rpms. The throttle body doesn't appear to be sticking in any way, so I don't think this is the cause. The car will also randomly raise and lower the idle without even touching the throttle or anything else. Anyone got any ideas? The ECU is chipped and the timing is set to stock. I have tried several chips, all with the same results.

 

Anyone?

 

iac valve