I haven't had the harness replaced, and it was exhibiting failure in numerous spots. However, I reconditioned it pretty thoroughly (wire brush, wire cutters, replacement wire, and electrical tape) and am fairly certain the problem isn't related to either the ECU or the harness. If it was I would likely be seeing problems all the time, and would have numerous other issues like no starts, rough running, etc.

The AMM is a possibility I have considered, but the car runs fine and idles like a champ. The only exception is when it is REALLY cold (we are talking sub 10f or so) when i t does this slow tach drift down thing. I wonder if it isn't actually a "by design" to keep the vehicle from stalling out in extremely low temperatures.

Of course the only way to check the AMM is really to replace it with a known good one, so its tough to know for certain unless I shell out for a replacement (which I should likely get anyway).

As for the IAC, I plan on cleaning it out per the FAQ when I get access to a warm environment (its cold on the old driveway right now).

Thanks for the post.

-rt