Sticky RPM

[diehard80's]

One of my '87 Rangers has a minor but odd issue with dropping back down to idle. Sometimes if I'm driving with the engine turning about 2k-3k rpm and I push the clutch down to come to a stop the engine will keep turning steadily at 2k rpm, even though I'm not touching the throttle. Then, it won't stop that until I let the clutch out just enough to bring the rpm back down to normal. From there it's fine. Has anyone had this problem before or does anyone know what would cause this? Throttle Positioning Sensor or idle control issue maybe?

 

[RustedRanger]

I would guess it's a IAC valve problem,get a new gasket and try cleaning it and the ports out. If you need a new one rockauto.com has a good price,that's where I got mine. If you unplug it while running it should die if the IAC is working. Also....it is a good idea to use some carb cleaner on a rag to wipe off the back of throttle blade,spraying the cleaner don't get it.

 

[diehard80's]

Okay, I checked for codes and found the problem: throttle position sensor. Apparently, when it goes bad, it also causes the truck to hesitate when driving at a steady speed and then jerk into working fine when you push the gas pedal to speed up.