High Idle and Shifting Problems

rewepython

Registered
Just to kill everyone's first response, I replaced the TPS. Twice (I dropped the first one, bought a second just in case that was it). The car starts fine, and idles up high for a few seconds then drops down to about 1100 RPM. When I step on the gas, it takes almost a complete minute to come back down, and when I'm idling down the street, I'm doing about 40-50 kph with my foot off the pedal. In order for the car to change gears, I have to play with the pedal with my foot to get it to shift.

I put a code reader on it, all it came back with was the TPS and EGR voltages out of range, and I just replaced the TPS. (Nuts if I ain't doin that bloody EGR, someone else can!). Car's a 93 (gen 1) mark viii. Help!
 
It wouldn't hurt, but I would also check for a vacuum leak. My '93 had 2 vacuum leaks and showed signs like that of a bad IACV with intermittent idling issues.
 
Tried the seafoam. All seemed to be going well, but as I burned off some of it during the idle after pouring in, the rpm's climbed back up to 1k+. I tried using some UV dye around all the vacuum joints but didn't notice any dye getting sucked into the engine, might have to try the brake cleaner method. I'll replace the IAC on Monday/Tuesday if it makes it through this weekend. Thanks for your help!
 
FWIW, the vacuum leaks I had were at the fuel pressure regulator and the EVAP system.
 
i was told that i have an IACV problem as well, my symptom is, when im sittin at idle the car will drop to about 600 rpm and rev up to 900 rpm back and forth..like it has an oversized crank in it
 
i was told that i have an IACV problem as well, my symptom is, when im sittin at idle the car will drop to about 600 rpm and rev up to 900 rpm back and forth..like it has an oversized crank in it

That could be a transmission valve body issue as well.

rewepython: I would say IAC for the weird idle.. take it off and try cleaning it. Are you sure you put the TPS on correctly? There is a proper procedure for it.
 
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