Stuck on fast idle

[sweet66monza]

Last night my 93 was stuck on fast idle when i got home. Shut it off and fired it back up and when I tapped the throttle the idle kicked back up. About 15 seconds later it shut itself off and wouldnt restart. Turns out it blew the fuse for the fuel shutoff solenoid.

Put a new fuse in and its still stuck on fast idle. Yes, the water temp is up and engine is warm. What should I check next? The chilton manual is basically useless.

Just to be clear, when I start it, it idles like normal, but when I push on the petal at all, it goes to fast idle, as it normally should when cold. But the engine temp is up. When I shut the key off the solenoid resets itslef

Thanks in advance!

 

[GenLightening]

I think the temp sensor to the left (as you're looking at it) of the IP controls the fast idle solenoid. It may be stuck in the "on" position. I'd check it warm and cold and see if it changes.

 

[icanfixall]

An easy short time fix is to lift the wire to the fast idle solenoid. I can't really say why the fuse blew but thats about the simplest way to get the truck off fast idle. And BTW thats how the fast idle works. That solenoid can't set the throttle because it too weak. But when you toruch the go peddle its setting the fast idle for you.

 

[jlwoods99]

I had a crossover line, ( fuel line) that was dropping between the throttle return and holding in fast idle. I had to reroute the line.

 

[sweet66monza]

I think the temp sensor to the left (as you're looking at it) of the IP controls the fast idle solenoid. It may be stuck in the "on" position. I'd check it warm and cold and see if it changes.

Ill have to go back out and take another look. The only temp sensors i recall are the one on the left head and the one on the left side of the motor under the vac pump.

I know the fast idle setup itself is working as it should (pushing the pedal), that is not the problem. The solenoid itself isnt kicking back off until shutting off the key.

And i know theres nothing obstructing the solenoid or throttle linkage

 

[sweet66monza]

Well this morning it stayed on fast idle for about 20 minutes and then kicked off. Truck sat at school all day and I went out to it. It was cold. Started it, tapped the pedal to kick up the idle, five seconds later the solenoid kicked off by itself. Truck sat at the girlfriends the rest of the evening. Went out there to leave, again, idled down 5 seconds after starting cold.

What activates the solenoid? Outside of cutting the wire loom apart to chase wires

 

[Fordsandguns]

There is a temp sensor on the passenger side, down kind of behind the thermostat housing. The harness to the high idle solenoid and to the cold advance connect to this sensor.

 

[icanfixall]

Thats where it is found. The problem now is getting to it. Lost of "things" needs to be removed for that simple sender..