Questions and Answers

Ford F-150 Stuck Fast Idle Q. I have a 1984 Ford F-150 manual transmission inline 6 300 engine. Its carbureted. It doesn't get driven much but lately I have noticed it will hold in high idle once in a awhile when I park and take my foot off the accelerator. The accelerator isn't sticking, I checked that.

But I think this high idle is contributing to the fact that when she is high idle and I turn the engine off she doesn't shut off right away and sometimes follows with a back fire. I have a couple ideas I haven't tried yet, such as working over the distributor or rebuilding the carburetor.

Do you have any ideas as to what is causing this? Your opinion would be much appreciated.

Thanks..

A. Chances are the choke is what is sticking on it and not allowing the engine to idle down. I would look over the choke linkage very carefully and make sure nothing is disconnected or binding. Also make sure the choke plate opens as the engine heats up. You may have a bad choke thermostat/heater. If all else looks good, try cleaning the linkage and spraying it with some penetrating oil. This should free up stuck linkage.

I would also check the base ignition timing to be sure that is correct. Any one of these will cause the symptoms you describe.