2.5L ('98-'01) High Idle

[Alam0]

I've been having high idle issues for a while now. When the engine is fully warmed it will idle around 1100-1200 RPM. When shifting gears the rpm's
don't drop. They only drop (very slowly) after I come to a complete stop.
The engine seems to run better with the IAC Valve unplugged, around 750 RPM. Normally when it's unplugged the engine should barely be running.

So far I've replaced the IAC Valve, EGR Valve, and recently the TPS Sensor. Changing the TPS seemed to help a little, but still having high idle issues.
I've done everything from checking for vacuum leaks and exhaust leaks. Everything seems good.

I should also point out a previous mechanic we took it to did a EGR Valve bypass by blocking it with a sprite can lol. I didn't know about this until after
I decided to replace it. I have a feeling that he had messed with the anti-diesel screw because he couldn't figure out the problem. I'm thinking of
messing with the screw to hopefully fix this issue.

If anyone has a different input on how to approach this I would love to hear it, Thanks.

 

[scotts90ranger]

From what I've heard somewhat recently it's likely the vehicle speed sensor or something related... the newer ones don't idle down unless the speed is below a certain point or something...