Discussion Starter · #1 ·
Here is my scenario... Last winter, here in NW florida, we got down to 15 degrees faren.. Went to fire up my truck, the idle was pushing 2500 rpm. it never did idle down. IAC was stuck in the open position. Removed & cleaned the TB & IAC, reassembled and installed. Same deal. super high idle RPM. Replaced with IACs from all major parts stores, same deal. I ended up manually adjusting the IAC to allow sufficient flow for spec idle and A/C useage. I got my hands on an OTC Enhanced scanner, the diagnostics identified all three components IAC/TPS & O2 sensors operating at voltage spreads of .28 & 4.28 which is way out of whack! It is obviously running in a default mode, but the efficiency isn't bad at all, still getting around 12-15 MPG. Any one ever have this coincidental issue or know if one bad component can affect the other? Im about ready to dig into the electricals, but since they are not all tied directly together before the PCM, I have a feeling my PCM may have bit the dust!