2.9L intermittent throttle sticking

[fox44]

Hey guys! I have been having a intermittent problem with my 92 ranger with the 2.9l and manual trans. The issue im having is that randomly the throttle will "stick" when I push in the clutch to shift. It will either stay at the same RPM or even climb up to around 3000-3500 RPM. Some times it will slowly drop on its own or other times it will stay high.When I do have this issue it is never consistent, it will happen several shifts in a row or for a whole day or just happen once. When it is happening I also notice that the throttle will also stick with the clutch out and almost act almost as cruise control and propel the tuck along with my foot off the gas. The issue started about 2 years ago and lasted intermittently for a couple weeks and then stopped for almost a year and then came back for a couple months and was very common. And then for no reason it stopped until last week when it started again. The ONLY thing that fixes the issue is if I disconnect the negative battery cable for a few seconds. When I start the truck again it wont have the problem for few hours or sometimes even a couple days.

I have tried everything I can think of and everything I could find on the internet. I have confirmed that it is not the throttle cable or gas pedal sticking and have cleaned the throttle butterfly and made sure it doesn't stick. I also replaced the TPS after having that recommended to me. Electronics have never been my strong point but the fact that disconnecting the battery resets the problem, even if only for a bit leads me to think it may be a computer problem maybe?

Thank you for any help you can provide and I look forward to helping answer any other questions I can on the forum

 

[RustedRanger]

Sounds like the IAC valve...Idle Air Control....lots of posts on the subject here. If that is the problem sometimes they can be cleaned with carb or throttle body cleaner.

 

[1989LongbedGT]

Try unplugging the throtle position sensor and drive it that way. I you free rev it will it hold its rpm and not drop back to idle?

IAC is for idle control. Which is usually closed during throtle operation. I can't picture it being iac at this time with how high of rpm you state

If it holds its rpm high in neutral try unplugging the sensor. If it drops to idle then check for proper voltage to and from tps.

 

[fox44]

Thanks for the replies guys. I tried cleaning the IAC valve with carb cleaner and no luck. To check voltage on the TPS I will need to borrow a volt meter next week from work. I will check it then and see what I get. A friend at work had a scanner and checked for codes on it and got nothing. But my check engine light has never came on so that doesn't surprise me.