Idles Too Fast

[Kroeter]

I have a 97 Ranger with 4.0 Liter V6 manual transmisson. After a few minutes out on the road the idle likes to kick up to about 3000+rpm. I can actually take may foot off the gas and maintain about 55-60mph. This doesn't happen right after I start it, just usually after on the road for a little bit. I can not kick it down by simply hitting the accelerator.

Is it a sensor, stuck accelerator?? Any ideas is appreciated!!

 

[MountainMike]

On my 93 I had a similar issues with the idle. I changed the PCV, checked the plenum for leaks, changed out the IAC and cleaned out my throttle body. I even ran the throttle body through it's full range of motion and could not figure it out. Turns out on the road somehow the cruise control cable was binding causing it to pull up my RPM's. If you're vehicle I equipped with cruise it is something I would check. My cable is just pulled, may replace it later on.

 

[Kroeter]

Do not have cruise control. Did have an issue with my coolant being low and temp gauge running a little warm. added coolant and temp seems to be running normal. It usually only does it in the morning after it warms up. Don't notice it as much in the afternoon.

Could it be a thermostat issue?? Thanks!!

 

[MountainMike]

I don't think so but maybe someone could chime in. Did you check for vacuum leaks?

 

[Csechols]

My truck does this too. the only way i can get it to stop revving up when letting off the gas is to shut the truck off and restart it , even then it starts doing it again after 10 minutes.... i have boughten a new iac which didnt do anything. new egr, mines a 3.0 190000 manual tranny.....i know my throttle is not sticking.

 

[Kroeter]

I notice it more if I run the heater/fan. If I leave it off the idles "usually" stays down, this is why I'm wondering if it is a thermostat issue??

 

[xentris02]

i had the same problem last winter into this summer. i have a 93 and it was throwing codes only on the highway and it threw iac codes the most but never the code for the sensor that was the problem. i ended up replacing the iac and when it still happened i gave up for 2 months then i checked codes still iac so i ended up reading some thing on here and well went to junk yard to get a used tps (to test my theory)to see if that was it and it was. havent had a problem since. i sujest buying a new one if you have the money thou.

 

[Kroeter]

Thanks. I think I finally got it. I cleaned out the throttle body,looking for the cheap answer. Didn't really help too much. Changed the IAC and bingo.... problem seems to be solved!!! 230,000 miles and running like new....."Knock On Wood"!!!