High Idle? New idle motor? 1994

I have a 1994 Olds Eighty-Eight Royal with 115,000 miles on it. Within the last six months, I have replaced tires, brakes, alternator, starter and battery. The one problem we haven't been able to solve is a non-constant high idle. Sometimes when I start the car, it is reving really high and will "drive" itself with out me touching the gas (this works both forward and reverse). The brakes become a bit tough to press and when you shift the car to park, it just growls as the idle spins out of control. If I kill it and restart, it will be just fine. So unfortunately, this has meant that the shop has been unable to figure it out because it won't do it for them. We replaced the PCV value and some hoses but it hasn't helped. They are suggesting a new idle motor - to the tune of $250 which I just can't justify because they are also not sure it will fix it. They say if it is not the needing of a new motor than it is the computer and my car would be unfixable.

Any ideas? I am still driving it as is and just restarting if it starts on a high idle....

Thanks!

Welcome to AF!!

Check the car for a vacuum leak. It could be anywhere on the engine. Usually vacuum hoses will become brittle and crack and you can't even see the cracks but air can get in. Also check the intake manifold gaskets as they too can be a source of the leaks. I suspect once you correct this the idle will return to normal.

Welcome to AF!!

Check the car for a vacuum leak. It could be anywhere on the engine. Usually vacuum hoses will become brittle and crack and you can't even see the cracks but air can get in. Also check the intake manifold gaskets as they too can be a source of the leaks. I suspect once you correct this the idle will return to normal.

Thanks for the welcome!

See, I think that my mechanic did this but I guess I don't know enough to check on my own. Do you think that the idea of needing a new motor is just false?

I've never heard of an idle motor on the 3800.

Try cleaning the IAC (Idle Air Control valve) if the mechanic hasn't already. http://www.lesabret.com/phpBB/viewtopic.php?t=4054

Next, check the voltages on the TPS (throttle position sensor) as it may have a "dead" spot. http://www.lesabret.com/phpBB/viewtopic.php?t=1720

These links are for a slightly older version of the 3800, but they should be close. The voltages may be different on a 94 so you may want to do a forum search just to verify them.

i had the same problem i just replaced the (IAC) idle air control valve and the (TPS) throttle positioning sensor but you will have to take off the throttle body its not easy i had to cut a wrench in half and that was still hard ... :(