High Idle

Rooster71 · 02-04-2012, 01:58 PM

I have 02 with the 4.7 engine. For past week I have noticed that the idle climbs when I am sitting still in park. It does not go extremely high, but high enough that it is noticeable. It will stay that way for a few seconds and then drop. It will do this several times until I start driving. I have not noticed anything while I am driving. Any ideas where to look?

Jeepgcl9947 · 02-04-2012, 02:40 PM

I have the same problem. I've fixed like every sensor, and still does it!

maloj2003wj · 02-04-2012, 02:59 PM

I had the same problem with my 4.0L . My mechanic changed the IAC first, but it still happened. I changed my TPS sensor myself today and cleaned the throttle boddy. It stopped. Hopefully won't happen again. If it does I'll let you know. The car runs much better after cleaning the throttle body though!

**Gran_Paradiso** · 02-04-2012, 03:00 PM

When mine did that I changed the TPS (Throttle Position Sensor). Inexpensive easy fix.

Jeepgcl9947 · 02-04-2012, 03:06 PM

I have the same problem. I've fixed like every sensor, and still does it!

maloj2003wj · 02-04-2012, 10:15 PM

Quote:

Originally Posted by Jeepgcl9947

I have the same problem. I've fixed like every sensor, and still does it!

Have you checked for any vaccum line leaks?

Jeepgcl9947 · 02-04-2012, 10:22 PM

Quote:

Originally Posted by maloj2003wj

Have you checked for any vaccum line leaks?

Yeah, over and over again.

piraterig · 02-05-2012, 02:41 AM

mine does this occasionally in park. 04 4.0

Bkhager · 02-05-2012, 08:30 PM

Quote:

Originally Posted by piraterig

mine does this occasionally in park. 04 4.0

I swapped motors in my 96 xj and I'm being plagued with high idle. Changed iac, tps and checked for vacuum leaks, still no fix!

OTownDaddy · 02-10-2012, 09:30 PM

I have the exact same issue. Causes a clunk when I shift out of park if the rpms are up do to the tranny engaging at the higher rpm. So the list of fixes are (from what I gather here):
* TPS replace
* throttle body cleanup
* vacuum leaks

So, wouldn't you notice other problems if it was a vacuum leak?

I was also wondering, what is the order of the list with respect to cost? TPS cheapest, then throttle body? What about in terms of difficulty?

maloj2003wj · 02-11-2012, 06:04 PM

Its all pretty easy the tps is like $35, you can replace it without cleaning the throttle body, but i would suggest you do. You would also need the throttle body gasket if you are gonna do it. Well if you have a 4.0 if 4.7 its reusable. The gasket is like $3.0

so its all pretty cheap. In terms of difficulty its all pretty easy as well you just need the right tools. Heres a detailed description on how to do it http://www.wjjeeps.com/service/tbody.htm

Let us know what the result is