85 F-250 idle problem?

Question

I have a 85 F-250 4x4 it has the 302 with EFI. I am having problems with the truck ocasionally idling exessively high and at other times stumbling and stalling. Also started to have a strange problem with the engine cutting out when in drive Driving along @55 it will just like cut out if I mash the gas pedal it will downshift into a lower gear and fire back up When this happens if I slip it into Neutral I can rev the engine and it sounds fine tho.Any Ideas? One person thought it might be the throttle position sensor? Where is that at on the back of the plenum?

Answer 1

If your looking for the tps sensor, it is located on the bottom of the throttle body. The throttle body has to be removed to change it.
It seems odd for a 302 to be in a F 250, it might be a 351 windsor.

Answer 2

That era Fords were notorious for ground problems. I would check the main engine ground connection. Make sure it is free of corrosion and tight. A loose ground can cause all sorts of problems, including the ones you describe. If it is not the ground then I would check the idle air control motor located in the throttle body, the throttle position sensor and the fuel pump (pressure and volume). From your description of problems, I would be willing to bet you find a ground problem.

Answer 3

yup the throttle position sensor should do the trick. It should be located on the top of the throttle body. Try doing a tune up too it might help also. Walmart has spark plugs for cheap autolights

Answer 4

I have an 87 EFI 302 (5.0 L). Almost always, this problem is a vacuum leak. Please, check ALL the hoses for cracks and splits or just being blown off by a backfire. The biggest culprit is the power brake hose.

Answer 5

Hope nothing happens to it through the end of the year and buy a 2007 Toyota Tundra in January if you have the extra change. I guarantee you'll love it.

Answer 6

it ia ford they were built to GO and do not like to idle around