6

I have a 1999 Ford Ranger pickup with about 242,000 miles on it. After driving for 10-20 minutes the throttle will start to stick when I take my foot off the pedal. After a couple seconds, the engine RPM will begin to decrease and return to the idle.

What can cause the throttle to stick and what are the ways I can troubleshoot the issue?

Thanks

  • 1
    Just for reference, how old of a Ranger are we talking about? (age, milage) – anonymous2 Oct 1 '16 at 20:00
  • That would actually be very important to know, I suspect that the throttle management system has changed over the years. Do current Rangers still have mechanical throttle linkages? – dlu Oct 1 '16 at 20:43
  • 1999 Ford Ranger with ~242k miles – wbeard52 Oct 1 '16 at 21:29
  • Based on the mileage it seems worth checking the condition of the throttle body. – dlu Oct 1 '16 at 21:31
  • Saw the question title in "Hot Network Questions" and my first reaction was "is it your foot?" – jedd.ahyoung Oct 2 '16 at 3:57
4

The time involved makes me suspect something heat related. I'd suggest opening up the hood and seeing if you can get access to the throttle body, it will probably look something like this:

Throttle Body

The throttle cable is the part leading from the green plastic bit towards the upper right to the brownish quadrant near the middle of the image. Have somebody sit in the car and move the gas pedal to see if you're looking at the right thing. Once you find it look carefully to see if you see anyplace where the cable might hang up. If you do this when the engine is hot and the problem is happening you may see that the cable doesn't respond immediately when the throttle is let up.

The problem could be something that is hanging up the cable, or it could be a build up of gunk inside of the throttle body. I'm kind of leaning towards the latter since that is a part where you might reasonable expect both close clearances and heat to change the fit. If you pull the inlet hose (the black item leading to the lower left in the photo, you may be able to see if there is a build up in the throttle body.

I suppose another possibility might be the throttle position sensor (TPS, if there is one). If it was slow to return after the throttle was released the ECU might continue to provide fuel and the engine might be slow to return to idle. This assumes that the TPS is independent of the throttle shaft and has the option to return at a different rate (or it could be what is hanging up the throttle).

Here's a link to a pretty good video of a fellow walking through the process of cleaning the throttle body of a Ford van.

1

Most likely the idle air control valve is hanging open after the engine warms up and kicks out of enriched mode. Ive seen this on a lot of rangers and Taurus that have came through my shop. Its definitely worth checking the condition of the throttle body as was previously stated and open the throttle plate to clean any build-up around it. But just from my experience with vehicles having the same symptoms I'd be willing to wager the idle air control valve is your culprit.

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.