1995 850 Engine Revving up on start

zanemw · Post by **zanemw** » 04 Jul 2014, 09:33

The engine is revving upto 3 and 4 when I start it up and I can hurry up and shift it into reverse or drive and it stops revving and goes to normal, as soon as i put it back in park it is revvs back up. It seems to be giving it gas in drive when i'm not pressing the gas pedal.
I just replaced the PCV system.
I cleaned the Mass Air flow Sensor
Cleaned the Air Control valve it only moves left and right a certain distance is it suppose to spin all the way around? I think it might just be all the way open how is an AIC suppose to move?
I unplugged the Air Control valve and it still goes crazy on start up.
I have heard the Throttle position sensor can cause problems, can it do this?
I did get some antifreeze on the engine when replacing the PCV I had to take off the upper hose to get to the bolts on the intake manifold, but I'm not seeing anything weird on the temperature.

zanemw · Post by **zanemw** » 04 Jul 2014, 09:38

I was checking it out with the engine off and the Air control valve is rattling really heavily and making a humming noise its so hot I can barely touch it without getting burned.

AVIP · Post by **AVIP** » 04 Jul 2014, 17:58

Sounds like a bad tps. Cheapest repair at this point. Sounds like the initial revving by the tps is causing the Iac to get hot because it wants to idle high my guess.

AVIP · Post by **AVIP** » 04 Jul 2014, 17:59

Any codes?

zanemw · Post by **zanemw** » 04 Jul 2014, 19:25

No codes are coming up, kind of weird. Im going to replace the throttle position sensor and check the temperature sensor out.

zanemw · Post by **zanemw** » 12 Jul 2014, 16:36

It ended up being the throttle position sensor, after replacing it worked fine.

AVIP · Post by **AVIP** » 12 Jul 2014, 18:07

Good news

had the same issue on a friend's Volvo I fixed. Assumed it was the same!