Explorer Revving Problems

[savvy5473]

When I hold the throttle steady on my 1994 explorer 4.0, the engine RPM will go up and down by 500 rmp while at steady throttle. This occurs at any RMP and I can feel it even when driving down the highway at a steady speed I can hear the engine revving up and down when at steady throttle. When at idle it idles perfectly smooth.

any ideas?

Thanks,

Shane

 

[Dlee6204]

Sounds like your Throttle Position Switch is bad.

 

[huntman58]

I confer on the TPS!

 

[savvy5473]

For some reason I had my brain set on vacuum problem, however I just took the TPS off an engine I have spare and swapped it. Low and behold it fixed the problem. Thanks guys!

 

[djembeing]

Is it hard to change?
My 99 ranger 4 cyl 5 sp does something weird. Sometimes, when i press the clutch or have it in N, it'll rev up to 3k or 3500 (more sometimes). After a few seconds, it'll go back to a normal idle. Or, sometimes i'll let out on the clutch a bit just to get it to calm down. Usually happens at stop lights. It's done it since I got it.

 

[skderen]

It's not that hard to change. It's located right on top of the block, so it's very reachable. And it's only held on by two screws (and of course you have to detach the sensor connector.)
Biggest problem that I ran into when I changed mine is that the screws were original, stuck in there good, and made of a "softer" material - maybe lead-alloy or something?. I had to be really careful to not strip them, which required some creative toolwork.