I bought my used '99, 4X4 lariat , about a month ago with 59K miles on it. First off.... I love the truck.
I've been having problems with the idle. My symptoms include an intermittent "bad" idle. Normally, when all is well, the idle jumps high for about 3 seconds.. then kicks back down to normal. (from the tach). When ornery, my idle kicks high and immediately falls to stall. This will persist until I continuously start it and/or brake drive it. Then all is fine. Does ANYONE know what this might be? The dealership is closed today (memorial day) and I'm p.o'd.
Throttle body? Sensor? ??

Thanks for your input, ahead of time.

 

Hi Koogrr,

Your problem could be just about anything, from something as simple as a clogged fuel filter (repalce it immediatley anyway, it never hurts & could clear this up for you) to a bad IAC (idle air control) to a dirty MAF (mass airflow meter) to EGR, ECU or other of a number of different issues.

Whatever you do, don't "brake torque" it to drive it, as that will put a *termendous* amount of additional heat in the automatic transmission and burn up the fluid in no time.

This needs the attention of a properly trained service technician, so I'd advise either taking it back to the dealer you just bought it from a month ago if they gave you any warranty on it, or take it to a good Ford dealership service department and have it looked at, and put an end to your frustration and just get it fixed correctly.

Sorry I'm not of more help to you, & good luck!