GMC Repair: 1990 4.3 Litre GM Engine, gm engine, intermittent fault

Question
I Have A 1990 GMC HaLF tON wITH a 4.3 lITRE eNGINE wITH 135000 Miles.The Engine Has Had On Major Work Done To It.It Will Not Idel When Cold.I Have Cleaned The Throttle Body . The Idel Air Con. Valve Is Working.The EGR Valve Is New.The Cold Water Sencor Is New.What Is Left.

Answer
Could be a faulty INTERMITTENT fault of the TPS or the Air Temperature sensor or several other components.

Did you follow the manufacturers recommended preset of the IAC BEFORE you re-installed it ?> If NOT, This can cause damage to the IAC and or the IAC SEAT within the throttle body where the pintle (conical) valve of the IAC rests.


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