What's up gurus,

Help me diagnose this issue. I'v been having an idle hunting issue for a while when the car is in park and in neutral. When I put it back into gear it idle almost fine.
I received no engine codes. I replaced the Maf, O2, Map, spark plugs and ignition coils and they did not solve the issue. I know its not the tune.
So 2 and change years ago when I started my Rotrex supcharger project I bought a used throttle body from the junk yard and its been knocking about in the garage.
I decided to clean it up and swap it with my existing one. Low and behold when I started the car, my idle was purring again. Problem solved!!!!!

The car drove normal until just now. I did a few WOT's to test my new 85mm pulley out that would give me max of 13psi with the AEM water/meth kit that I installed. The car pulled well and ran 10.1-11.1, so I know I need to tune some more.

Here is the issue, as I came home and put the car in park, the same Idle hunting started again. I am so dissapointed.

Did I screw up the IAC in the other throttle body? What could have caused that? Or was the other one on its way out being that I did pick it up from the junk yard from another 97 E320? I am reluctant to buy a new one and worried that the same thing will happen to that one. Please advise if it is possible that the second one was on its way out and what should my diagnostic be? What is the recommended torque for the throttle body bolts? Possibly not torqued properly and the pressure is causing air to bleed out from the seal?

Oh boy the questions I have. I need some direction here....plz.

Rock

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