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DESCRIBE ISSUE.... idle runs high, I done a smoke check for vacuum leaks, fixed. I have changed the spark plugs, ignition coil packs, crankshaft position sensor, MAF sensor, intake gaskets, valve cover gasket, pcv valve, throttle body gasket, new throttle body and did the relearn procedure about 20x. Did a compression test, everything good there, also a block test for a bad head gasket, that's good no leaks. I'm running out of options, I think my MAF sensor might be bad. I'm not sure what to do next and or check. Your guidance would be much appreciated.
Have you tried blocking the vacuum line to the power-brake booster? What is the hot idle speed now, in neutral with A/C off? If the idle is really higher than I (or the PCM) expect it to be, the first thing to determine is where the extra air is coming in. You block the IAC inlet port to see how that effects the idle speed. No effect? Then block the PCV and brake-booster lines to make sure one of those isn't a big leak. After that, slide a block of wood across the TB opening, if that doesn't kill the engine then you know there has to be a vacuum leak somewhere; you gotta keep checking. Got it? There is only one way the idle can be too high... too much air getting in; and there are only five ways for it to get in (IAC, throttle, PCV, brake, "other"), we need to isolate which path the air is going and focus there.
Is this an "electronic" throttle system? I hope not, the possibilities get more complicated if the problem is in the IAC/TB assembly.