I recently had a tune up done my crusty stock 94 si
replaced the cap, rotor, fuel filter, plugs, new oil, etc.
everything was cool and car ran great until I added some slick50 fuel systems cleaner to a tank of new gas. Ever since then my car has been idling at around 1100 rpm, before it would idle at 725 or so. Will the fuel cleaner crap do this?
Also at the same time I did that I sprayed that throttle body/intake/carb cleaner stuff into the throttle body and wiped down as far as I could go.

 

the fuel cleaning in the tank probably will not affect the idle at all. but since you sprayed that intake cleaner intot he T/B you might have done something to make the throttle place stick open a little.......or maybe some dirt or somthing went into the IAC valve.......

check to see that there is no obstruction holding the throttle plate open slightly and maybe give the ECU a reset and see what happens from there......

good luck.....

 

where is the IAC valve and how can I check it for blockage?