Tps???? - Ford Forums - Mustang Forum, Ford Trucks, Ford Focus and Ford Cars

08-09-2001, 21:56

okay, here's the problem. whenever i run my panel vents or a/c, my car develops and idling problem. i'll try and describe it as best i can so please bear with me. while sitting with the a/c or fan on, my car starts idling faster than normal, usually hovering just over 1000rpm as opposed to under 1000 normally. when i'm driving, no matter what speed or what gear, it feels like the rpm's are trying to take off. and when i step on the clutch the rpm's jump. the last time i had it on, it reved up to almost 4000 rpms and hovered around there for about a minute until i shut the car off. so i shut the fan off and started it up again and it never did it again. i've played with this the last couple times wether its panel vents, heater, a/c everything. any body got any ideas???? if this isn't clear enough just ask and i'll try and explain it better.

thanks
Chris

08-10-2001, 02:38

Well, I'm not sure if Tempo's have one but that sounds like a bad idle air by-pass valve. It's a valve that opens to allow air into the intake to increase the idle rpm while the a/c is on. Hopefully someone else here can clarify this one for me.

GuillermoXR5i · 08-10-2001, 10:37

Yes, Tempos both HSC and V6 have it and it could very well be bad. Check the TPS as well. Use a multimeter or ohmeter. Touch the leads of the sensor and hold them steady. Then have someone give it throttle to WOT very slowly. If you see any jumps in the multimeter or the resistance is out of range you know you got a bad TPS. There's also a certain resistance the Idle Air Bypass Valve's solenoid is supposed to be at when not energized. If it's out of the range then it's bad. Hopefully someone knows what the resistance is supposed to be for the IABV.