post #1 of Old 06-24-2010, 08:49 PM Thread Starter
davekippen
Registered User
1999 TJ Wrangler 
 
Join Date: Jun 2010
Location: Michigan
Posts: 11
RPM Revving issue

My 99 Wrangler 4.0 started having RPM issues about a month ago. Sporadically the RMP's jump way up for a while then go back down to normal idle RPM. It happens when sitting at a light in drive and also if it is in park, just idling. It often revs way up when i put it in park after stopping. Thoughts?

davekippen is offline  
post #2 of Old 06-26-2010, 06:16 PM Thread Starter
davekippen
Registered User
1999 TJ Wrangler 
 
Join Date: Jun 2010
Location: Michigan
Posts: 11
Anyone?
davekippen is offline  
post #3 of Old 06-26-2010, 06:20 PM
1fastR
Registered User
 
1fastR's Avatar
1998 TJ Wrangler 
 
Join Date: Jan 2006
Location: Ardmore, Tn.
Posts: 671
How old is your battery? I had a somewhat similar issue once and my battery was going bad. It could be a vacuum leak as well. Have you replaced the exhaust manifold or anything lately?
1fastR is offline  
post #4 of Old 06-26-2010, 06:23 PM
HerkEng
Registered User
1971 J-Series Truck 
 
Join Date: Jul 2008
Location: Boise, ID
Posts: 2
When did you last clean your throttle body and IAC?
HerkEng is offline  
post #5 of Old 06-26-2010, 06:24 PM
Jerry Bransford
Administrator
 
Jerry Bransford's Avatar
2004 TJ Wrangler 
 
Join Date: Jan 2003
Location: Escondido, California
Posts: 64,008
A vacuum leak is often responsible for high rpms, has anyone worked on or around the intake manifold lately?

Getting Savvy...

When you have a choice, buy American.
Jerry Bransford is online now  
Reply

Tags
high rpm , vacuum , leak


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page



Similar Threads
Thread Thread Starter Jeep Forums Replies Last Post
Engine revving up when braking? chefdab TJ Wrangler Technical Forum 22 11-29-2011 04:37 PM
Revving out when Started jeff83 TJ Wrangler Technical Forum 3 05-09-2009 11:43 AM
4.0 stalling after revving choeyreplied TJ Wrangler Technical Forum 1 11-06-2008 11:57 AM
revving at start up?? attackcammel TJ Wrangler Technical Forum 2 09-11-2008 10:22 AM
Jeep Revving to high cspoffroad TJ Wrangler Technical Forum 3 01-04-2005 04:47 PM

Posting Rules  
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are On
Refbacks are On

For the best viewing experience please update your browser to Google Chrome