I have a 97 Wrangler. The other day it started to idle high. It Idles at 2200 rpm. It is not speratic. It runs just like it should but at 2200 RPM. I think it may be a vaccum leak somewhere but I looked everywhere and couldnt find one. Another thing that is puzzeling me is that I have no check engine light on. I did some tests on the Throttle Position Sensor and ruled that out as the problem. Any suggestions would help out greatly, I am stumped on this one.
Hey thanks for the reply. Yeah, I cleaned the throttle body out really well. Seems to be closing and operating correctly. I was pointing to the IAC. Do I clean out the motor or the sensor or what?
06-18-2010 01:25 PM
Also, wouldnt the IAC cause the check engine light to come on?
06-18-2010 01:40 PM
It might. Or not. You might have a slight leak in the intake manifold somewhere, as well. That will cause the throttle to race, but otherwise respond.
06-18-2010 01:42 PM
Clean out everything in and around the IAC including the passage inlet.
Q-tips work well for this.
Sometimes it will throw a check engine light, sometimes not. Bad sensors can fly under the radar sometimes.
06-18-2010 01:44 PM
Sounds like a plan. I'll give it a shot this weekend and see what I can come up with.
Thnaks for the input guys. Much Appreciate.
06-28-2010 01:57 PM
Well, back to the drawing board. I cleand out the IAC valve and housing at with no effect. I did the TPS voltage test and it came back like this. 5V Incoming voltage. Which is correct. I did the output to test and at WOT it only read 3.9V when I was opening the throttle. I couldnt get it to go over 3.9V Should the range on a proper TPS get me closer to 5V? Does anybody know what the proper Volt range is?
06-28-2010 02:06 PM
Has the intake manifold been worked on or removed/reinstalled? As would happen if the exhaust header was replaced.
06-28-2010 02:15 PM
Yes it has, It was replaced about two three years ago but I found no leaks anywhere on or near the manifold...
06-28-2010 02:18 PM
Leaks are often hard to locate but my guess, since you have already cleaned the IAC, is a vacuum leak. How about spraying some WD-40 at where the intake manifold bolts to the head while the engine is running to see that makes the engine rpms change.
06-28-2010 02:22 PM
Been there. Like I said... Couldn't find a thing. It is very frustrating!!! Jerry, do you know if I should be getting an output reading higher than 3.9V at wide open throttle?
06-28-2010 02:24 PM
I'll have to see if my FSM (factory service manual) gives that information but it's at home, I'll look tonight if no one else answers that question by then.
06-28-2010 03:14 PM
You rock Jerry... Thanks!
06-28-2010 03:39 PM
It is supposed to gradually increase up to 4.5 volts at wide open throttle.