IvanFiveLiter

started up the car today idles at 900rpm normally. Tapping the gas every now and then to warm it up a little faste its 20 degrees here in new york haha. Rpm's going up to about 1800 max, proceeded to drive and at red lights id notice the car was idling a bit louder in neutral around 1400-1500 rpm. Kept doing it stopped got out sto see if it would stop and it didnt. Im going to my friends shop tomorrow toe get it taken care of along with other things. I think its the throttle sensor or could it be a vaccum leak? The oem tach is wrong liek ive heard on most foxbodys idles at 1200 rpm and idles 900 on my phantom big tach. Idled at about 2000 on the oem and 1500 on the big tach after this little issue

94redGTConv

Sounds like a vacuum leak or a tps out of wack, could be both have you done anything?


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petrock

I think its a bad IAC sensor. It controls the amount of air going into the throttle body when at idle. If it is stuck open then you will get higher RPM’s at idle. A vacuum leak between the throttle body & the lower intake could also cause this problem possible.

A throttle position sensor is pretty easy to diagnose with a scan tool available at most auto parts stores. It will tell you what %’g the computer thinks the throttle is at. If its not 0% when your foot is not on the pedal then the TPS is bad. You could also do a voltage drop test on the sensor and its wiring to see if its off.

Good luck...

IvanFiveLiter

yea i called my friend (mechanic) and he said right away that its probably a vaccum leak. tps? is that for throttle pressure sensor? Done anything? If you mean have i done anything about it no but i am getting it taken care of in about 10 hours from now lol. i will be heading to my friends shop in the morning.

petrock

TPS is Throttle Position Sensor

dawson1112

Lol seems to be a plague of idle issues lately on here.
Clean the idle air control valve. Check for any kind of vacuum leaks, including any leaks after the maf in the air intake tube. If it sucks air after the maf the air is unmetered and the eec thinks there is not enough air being taken in so it will open the iac a bit more.

Js88lx

Tell me about it dawson....LOL