caliplaya650-
If the code 66 didn't reoccur during KOER, then it's an old code. You mentioned the TB whistling. You need to isolate this. Air entering the system after the MAF can trip a code 66, and since it didn't come back during KOER, I don't think it's a wiring problem. Make sure there aren't any leaks after the MAF, disconnect the neg battery cable, turn on the headlight switch (to discharge any capacitors), turn it off, attach the neg battery cable, and perform a KOEO test. It should pass. Then perform another KOER test, and post the results.
Take care
~Chris
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RACECAR spelled backwards is RACECAR
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