Idle RPM surges to 6500+

[ekennedy2]

My car 1994 300ZX 2+2 automatic transmission with over 186k miles
This is an intermittent issue. This only happens within 10 minutes of engine start (cold engine). With the car in drive and the brakes applied for a STOP sign or red light the engine idle suddenly goes from the normal range to 6500+. Sometimes placing the transmission into neutral will cause the idle to return to normal. Other times shutting the engine off solves the problem. I have taken the car to two local Nissan dealers but neither one been able to solve the problem. Thanks in advance!

[itsa300zx]

For your engine to rev that high, the throttle must be opening somehow.
Search "stuck throttle" may reveal that the PVC tube next to the TB linkage might have popped out enough to cause this.

[itsa300zx]

http://www.twinturbo.net/net/viewmsg.as ... dtSearch=3

[ekennedy2]

Thanks I will check this out - hope its this simple.