High pitched whine when I let off the gas. - JeepForum.com
Search  
Sign Up   Today's Posts
User: Pass: Remember?
Advertise Here
Jeep Home Jeep Forum Jeep Classifieds Jeep Registry JeepSpace Jeep Reviews Jeep Gallery Jeep Clubs Jeep Groups Jeep Videos Jeep Events Jeep Articles
Go Back JeepForum.com > Models > Jeep Cherokee & Comanche Forums > XJ Cherokee Technical Forum > High pitched whine when I let off the gas.

FS: Wrangler RGB Multicolor Fog Light LEDs: Awesome EffectFS: 2007-2013 Jeep Wrangler "HALO" Angel Eye KitRockridge 4WD IS Taking Zone Offroad Suspension Lift Kits

Reply
Unread 12-13-2012, 06:22 PM   #1
deitzberg
Registered User
1998 XJ Cherokee 
 
Join Date: Apr 2012
Location: saylorsburg, PA
Posts: 112
High pitched whine when I let off the gas.

I have a 98 xj with a straight six. When ever I let up on the gas pedal I hear a high pitch whining. As soon as I hit the has even in the slightest it goes away. I did just have a new exhaust system put in so its actually a lot quieter so I dont know if it was there before as well. Any thoughts?

deitzberg is offline   Reply With Quote
Unread 12-13-2012, 07:23 PM   #2
CCKen
Web Wheeler
 
CCKen's Avatar
1999 XJ Cherokee 
 
Join Date: Jul 2011
Location: Canton, MI
Posts: 1,970
Quote:
Originally Posted by deitzberg View Post
I have a 98 xj with a straight six. When ever I let up on the gas pedal I hear a high pitch whining. As soon as I hit the has even in the slightest it goes away. I did just have a new exhaust system put in so its actually a lot quieter so I dont know if it was there before as well. Any thoughts?
Is this with the Jeep in motion, or standing still? Is the whining definately coming from the engine?
__________________
If we have data, letís look at data. If all we have are opinions, letís go with mine.

Man who stands in front of Jeep gets tired. Man who stands behind Jeep gets exhausted.
CCKen is offline   Reply With Quote
Unread 12-13-2012, 07:39 PM   #3
deitzberg
Registered User
1998 XJ Cherokee 
 
Join Date: Apr 2012
Location: saylorsburg, PA
Posts: 112
Both. Its not the belt I just replaced it a few thousand miles ago and I just made sure it was tight. It seems like it is coming from the front.
deitzberg is offline   Reply With Quote
Unread 12-13-2012, 07:52 PM   #4
CCKen
Web Wheeler
 
CCKen's Avatar
1999 XJ Cherokee 
 
Join Date: Jul 2011
Location: Canton, MI
Posts: 1,970
If you hear it while the Jeep is not in motion, try raising the hood and adjust the throttle by hand while listening for the whining. Sounds like a vacuum leak in a way, but could be the power steering pump, water pump, or anything in motion.
__________________
If we have data, letís look at data. If all we have are opinions, letís go with mine.

Man who stands in front of Jeep gets tired. Man who stands behind Jeep gets exhausted.
CCKen is offline   Reply With Quote
Unread 12-13-2012, 09:21 PM   #5
Winterwheeler
Registered User
2009 JK Wrangler 
 
Join Date: Oct 2012
Location: Wabamun, Alberta
Posts: 65
A family 87 Cherokee Laredo also produces a high pitched whistling sound at idle once it's warmed up. Someone suggested it could be a leaking intake manifold gasket. I would like to know how to diagnose this issue and get info on how urgent it might be to deal with.
__________________
Nolo Secundi Carborundum Illegitimi
Winterwheeler is offline   Reply With Quote
Unread 12-13-2012, 09:35 PM   #6
wgirvine
Registered User
1992 XJ Cherokee 
 
Join Date: Oct 2007
Location: Rosamond, CA
Posts: 602
Hate to say this but a high pitched whine when you are running down the road and let off, usually means ring and pinion gears are worn.
__________________
The road goes on forever, the party never ends....
wgirvine is offline   Reply With Quote
Unread 12-16-2012, 03:57 PM   #7
deitzberg
Registered User
1998 XJ Cherokee 
 
Join Date: Apr 2012
Location: saylorsburg, PA
Posts: 112
Quote:
Originally Posted by Winterwheeler View Post
A family 87 Cherokee Laredo also produces a high pitched whistling sound at idle once it's warmed up. Someone suggested it could be a leaking intake manifold gasket. I would like to know how to diagnose this issue and get info on how urgent it might be to deal with.
that is what I am leaning towards as well. I just had the exhaust manifold replaced. I read somewhere that the bolt in the back sometimes comes loose a hair and causes the sound. I just sucks that I had the work done in ohio and I cant take it back for them to deal with it since I am in PA next to jersey.
deitzberg is offline   Reply With Quote
Unread 12-16-2012, 05:10 PM   #8
deitzberg
Registered User
1998 XJ Cherokee 
 
Join Date: Apr 2012
Location: saylorsburg, PA
Posts: 112
I just got done tightening all the bolts on the exhaust/ intake manifold. I let it warm up for 10 minutes and drove it for another 10 and I dont hear the noise. Hopefully that was the cure. I did find one bolt against the firewall on top that was a little loose. I will check back in at the end of the week for the final decision.
deitzberg is offline   Reply With Quote
Unread 12-17-2012, 12:48 PM   #9
Name
Registered User
1999 XJ Cherokee 
 
Join Date: Dec 2008
Location: U.S.
Posts: 10
@winterwheeler the easiest way to figure out if you have a vaccum leak is to start it, pop the hood, and spray the engine bay down with some carb cleaner or something similar. If it revs up you have a leak somewhere
Name is offline   Reply With Quote
Unread 12-17-2012, 04:12 PM   #10
OnTheFence
Registered User
 
Join Date: Oct 2012
Location: USA, USA
Posts: 434
Can you take a photo of the exhaust/ intake manifold bolt that was loose?
I hear this is common. I'd like to check mine!
OnTheFence is offline   Reply With Quote
Unread 12-17-2012, 04:25 PM   #11
deitzberg
Registered User
1998 XJ Cherokee 
 
Join Date: Apr 2012
Location: saylorsburg, PA
Posts: 112
I will post one tomorrow afternoon.
deitzberg is offline   Reply With Quote
Unread 12-17-2012, 06:25 PM   #12
mschi772
Web Wheeler
 
mschi772's Avatar
1997 XJ Cherokee 
 
Join Date: Apr 2012
Location: Racine, WI
Posts: 2,061
EDIT: deleted unnecessary reply
mschi772 is offline   Reply With Quote




Jeep, Wrangler, Cherokee, Grand Cherokee, and other models are copyrighted and trademarked to Jeep/Chrysler Corporation. JeepForum.com is not in any way associated with Jeep or the Chrysler Corp.