Fast Idle won't turn off

[Devin & Amy]

Fast idle won't turn off. 1980 MC9 - stuck in a parking lot. Any ideas?

[Dallas]

Disconnect the wire to the fast idle solenoid.

If that doesn't do it, you have an air problem... Disconnect the air to the fast idle cylinder... that will allow you to have low idle.

GL
IHTH
Dallas

[mc8 tin tent]

Devin/Amy
  Which engine do you have ,8v71 has a fast idle on the solenoid which maybe sticking this happened to us .check to see if the solenoid is on by placing a flat blade screw driver on the coil top center to feel any magnetism (shouldn't be any if the fast idle switch is off) remove the air line between the solenoid on the fire wall and the top of the engine,i then gave the valve a light ,but firm tap(ON THE BOTTOM OF THE VALVE-don't hit the coil) I cycled it a few times and no more problems(you can take this valve apart and clean it when your not on the road).
Good luck !
Dwayne

[Devin & Amy]

thanks guys.
I couldn't find the solenoid, so I shut down the engine, dumped the air and then the valve released. Restarted and no problem.
I'll be taking the system apart this wknd and cleaning it.
Thanks for the quick responses.
Devin

[Kwajdiver]

Just so you know,,,, the fast idle goes through two switches.  One on the bottom of the push pull parking air brake, and of course the other is the Fast Idle Switch.

Bill
1983 MCI-9