Hi Everyone,
My '99 Jetta III showed a p1582 code, Idle Adaptation at Limit. I was told that I will likely need a new throttle body, something about the TB being plastic and not adjustable. Should I insist the mechanic clean the TB and see if that works, before replacing it? Are there any other possible explanations for a p1582 code?
Thanks!

well my repair manual says quite a few things ill give you the easier ones to try first to see if it fixes it. check your fuel pressure regulator and residual pressure. clean your air intake system (mass air flow sensor screen to see if it has debris in it) check your exhaust system for proper sealing. and check all your vaccum lines for proper seals. thats what my manual gives me for trouble shooting for this code.

more than likely you will need a new Throttle Body. you could try cleaning it out, then doing a "Capacitor discharge" which is where u unhook both battery terminals and touch the negative and positive cables together for a few seconds. then clear all engine codes, and try adapting the throttle body again. that works about 50% of the time, if it doesnt then u need a Throttle Body.

get a can of throttle body cleaner and clean the throttle body and butterfly real good. the car will be sluggish to start at first but the code should clear in a couple days. mine did