i have a 1995 legacy with an AT ej22 non-turbo.

2 years back i had an unorthodox underdrive pulley installed on it in the last few months the idle has gradually not been the best when stopped with the transmission in drive. if i go to park or neutral it feels fine, but if it's in gear there are uncomfortable vibrations coming up thru the steering wheel and seat. it's at it's worst when the a/c or cooling fans come on.

i have gone to the dealer expecting it to be transmission related, but the mechanic says he could not find any fault, and says it's because of the pulley, which is causing the idle to drop 200rpms below what is norm (800-850rpms?). it's not something that u can adjust from the throttle body, but is a function of the ecu, which he cannot remap.

does ne1 have any similar experiences or comments they can share? the pulley has been a useful mod to this anemic engine and i hope to keep it on the car, but if there is no solution....