Idle races at startup.

[Sigurd Jarlson]

My 88 Ciera 3.8L has started racing(~1500-2000 RPM) at startup and won't come back down until I put it in drive or turn it off and on a few times. It didn't start happening immediately, but this symptom may coincide with my changing the plugs a month or so ago. As an attempt to fix this I changed the IAC and cleaned the port, but that didn't change anything....

Any ideas?

thanks

[Prospeeder]

sounds like a vacuum leak to me, broken vacuum hoses, bad intake gaskets, or throttle body gasket, forgot the oring on the IAC valve....

[Sigurd Jarlson]

thanks. I tried spraying some carb cleaner around to see if the engine would rev up, but only got a slight increase around the EGR. It does code for EGR, but I changed it out and the code keeps coming back......

[Mur]

Could be the Throttle Position Sensor

[Sigurd Jarlson]

Thanks. I actually bought one, but my TPS is on the underside of the throttle body, so I would have to completely remove the throttle body to replace it and I really wanted to try other solutions first....