Hey guys, was pokin around under my hood today, and saw this little guy. it looks like its supposed to contact the throttle lever there, but its obviously not... Anyone know what this thing is, what its supposed to do, and if its actually broken like i think it is? Thanks for any help!!

Oh yeah, and truck is a 93 F350 w/ N/A7.3

 

Thats your high idle. when you start you truck it should be runing aroud 1100 rpms for a few mins.

 

Hmmm... Yeah pretty sure its not doing that....

 

It could be an adjustment problem. I'd check the distance from the plunger to the throttle lever when it's warmed up, and again when the engine is cold right after started. If the distance is unchanged, it's bad, if the plunger moves out, it probably needs adjusting. It looks to me as there is too much distance between the plunger and lever, warm or cold. Mine is set at about 1/16" cold.

 

get up in the engine and look straight down between the alternator and the thermostat neck.
deep down in there is a sending unit. if the wire falls off like it usually does when the alternator is changed, you will not have cold idle or cold timing advance.

 

High idle Is only energized when water temp is below 130f

 

That pic was taken with a dead cold engine. hadnt run for over 24hrs. Ill check for that sending unit tomorrow, see what i find. thanks guys!

 

The solenoid could also be bad. On my van, the advance works but the idle solenoid doesn't. You can hear the engine is much louder when cold.

 

But was the engine or the ignition on?

 

Also note, the solenoid is strong enough to hold the throttle lever in place, but not strong enough to push the throttle to high idle. That is why in the starting sequence you have to step on the gas pedal. Hit the pedal, the plunger on the solenoid advances and holds the throttle at the high idle position.

To test its operation, with the engine cold, turn the key on and look the engine. It should then be touching the throttle lever. Push the throttle lever towards the back of the vehicle, the plunger should extend farther. Release the throttle lever and it should rest at the high idle position.

It can be adjusted by taking a wrench and turning the plunger to extend or retract it. As stated above, high idle is generally around 1000-1100 rpms. Depending on your idle and high idle positions, the gap when off will be different.