Idle surge done it all

[dave1948]

My 1998 RS eclipse 2.0 n/t idle problem remains a mystery to me. So far, following the guide lines in the tech area and shop manual, I have replaced the IAC motor, both O2 sensors, the MAP sensor and the ECU. Have checked out the TPS, and water temp sensor, and all vacuum lines, cleaned the EGRand replaced all gaskets . Yet the idle problems still persists. The engine will idle fine for days even week somewhere between 750-850 rpm, then the base idle will go up to1150 to 1200 RPMs and when any strain is put on the engine(IE) turning on the AC or turning the wheel at idle the RPMs go up to 1500 and remain there as long as the strain remains(leaving the ac on). When strain is removed drops back to 1150 RPMs. Have taken it to the local dealer and local shop and paid bucks for them to tell me they don't knowwhat the problem is. Someone mention the FIAV but I'm not aware of what that is. All ideas appreciated.

Thanks Dave

 

[Itzallstock]

5 Gallons of Gas and Match?
Not too familair with with 2gs but I had a similar problem. It ended up being a combo of the Cam angle sensor and the cam shafts i had were slightly bent? worn? Anyways, thoose three things got replaced and i was fine. So much for spending 1000 on ecu and other sensors
-Ben