tired of poor performance please help - 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 Grand Cherokee & Commander Forums > WJ Grand Cherokee Forum > tired of poor performance please help

FS: 2007-2013 Jeep Wrangler "HALO" Angel Eye KitTHE NEW! VANCO DUAL MODE 15Ē/16″ Big Brake Kit w/BlaFS: Wranger BRIGHT License Plate LED! Just $3! Great value

Reply
Unread 02-16-2014, 06:41 PM   #1
Jrboarder27
Registered User
2000 WJ 
 
Join Date: Oct 2011
Location: Boulder, Colorado
Posts: 1,003
tired of poor performance please help

For a while now I have been trying to chase down the cause of poor performance and getting quite fed up with it, I will try to explain every thing the best that I can . To start I cant tell if this is transmission or engine because it seems to have to drop to far down in gear and rev way high to get any extra power and from a stop it seems to be in to high a gear and revs more then it should before switching gears (does not feel like trans slipping). However if giving it WOT it hesitates quite a bit and that seems engine related to me. Now here is the kicker some time I take a drive and it has all its power back and runs great, but thatís rare, and I cant find any thing that coincides with the jeep running great and running bad.

Now here are a few other things that might be related. I use to have a rough idle that could be described as a shake every few seconds but I decide to clean the MAP sensor and the Air intake temp sensor and the shake went away but not the poor performance and its still a little rough when cold . I have a hissing sound from behind the dash that I canít pin point, but Iím sure its not the brake booster because I already replaced that and nothing changed. every once in a while ( maybe once a month I have trouble starting the engine until I give it some gas .

I have replaced the TPS with a Mopar and replaced the fuel filter with a microgard from Oriellys. I have cleaned the throttle body and the IAC and again no change. I have of coarse kept up on regular maintenance although sparkplugs time is getting close but Iíve been having issues since before this set.

Any help or ideas would be greatly appreciated

Jrboarder27 is offline   Reply With Quote
Unread 02-16-2014, 07:43 PM   #2
sprocket1200
Registered User
2001 WJ 
 
Join Date: Aug 2007
Location: bc canada
Posts: 172
what engine codes are present?

unless i missed it, the engine size would be helpful as well.
sprocket1200 is offline   Reply With Quote
Unread 02-16-2014, 08:04 PM   #3
Jrboarder27
Registered User
2000 WJ 
 
Join Date: Oct 2011
Location: Boulder, Colorado
Posts: 1,003
I knew I was going to forget that, 2000 4.7, and most annoying part is NO codes, I wish I had at least one that could lead me some were.

Sent from my Galaxy S4 using JeepForum
Jrboarder27 is offline   Reply With Quote
Unread 02-16-2014, 08:21 PM   #4
cr8zynelly
Senior Member
 
cr8zynelly's Avatar
2002 WJ 
 
Join Date: May 2013
Location: Wilmette, IL
Posts: 783
Would start with plugs and go from there. Check your coils when doin the plugs. Kill 2 birds with one stone. Then you can at least check those off the list.
cr8zynelly is offline   Reply With Quote
Unread 02-16-2014, 08:23 PM   #5
cr8zynelly
Senior Member
 
cr8zynelly's Avatar
2002 WJ 
 
Join Date: May 2013
Location: Wilmette, IL
Posts: 783
Quote:
Originally Posted by cr8zynelly
Would start with plugs and go from there. Check your coils when doin the plugs. Kill 2 birds with one stone. Then you can at least check those off the list.
Could also try an injector cleaner or sea foam. I would do plugs first.
cr8zynelly is offline   Reply With Quote
Unread 02-16-2014, 08:26 PM   #6
cr8zynelly
Senior Member
 
cr8zynelly's Avatar
2002 WJ 
 
Join Date: May 2013
Location: Wilmette, IL
Posts: 783
Also fuel filter if it hasn't been changed.

Good luck!!
cr8zynelly is offline   Reply With Quote
Unread 03-26-2014, 11:00 PM   #7
Jrboarder27
Registered User
2000 WJ 
 
Join Date: Oct 2011
Location: Boulder, Colorado
Posts: 1,003
Ok so time for an update. It turns out that I can get good V8 power like I should, but only if I restart the engine after its already warm, for instance, 15 minute drive, eat some lunch (also seems the engine needs to be off for 10 or so minutes) get back in turn it on and the thing flies down the road, I'm lost, the only thing I've done sense last post was replace the air intake temp senser. and it got me the power more often, but it still goes back and forth.
Jrboarder27 is offline   Reply With Quote
Unread 06-09-2014, 07:24 AM   #8
Jrboarder27
Registered User
2000 WJ 
 
Join Date: Oct 2011
Location: Boulder, Colorado
Posts: 1,003
Time for another update, I just recently replaced my crank shaft position senser do to random shut downs of the engine at 70 mph. I am happy to say that It dies seem that I have fixed that problem, and gained a bit of my performance back.
I am now currently looking in to the transmission speed sensors. I started to get some hard shifts and strange gear choices on the trannys part
Quick question, I know some of you have used a multimeter to check the ohms on these speed sensors, so I did the same and got .614m on one and .584m on another and I read on another thread that a new one reads at .54xxm. So if any of you have heard of this and can chime in that would be great.
Jrboarder27 is offline   Reply With Quote
Unread 06-09-2014, 08:22 AM   #9
99SK04GTX
Registered User
2004 WJ 
 
Join Date: Jul 2009
Location: Hampton Roads
Posts: 424
Go online to Advance Auto and use coupon code TRT30 for 30% off and a speed sensor is $21 (order online, P/U at store). Both are the same part number so just buy one and first put it in the rear (output) to begin. If no change move it to the front (input).
99SK04GTX is offline   Reply With Quote
Unread 06-09-2014, 11:48 AM   #10
Jrboarder27
Registered User
2000 WJ 
 
Join Date: Oct 2011
Location: Boulder, Colorado
Posts: 1,003
Quote:
Originally Posted by 99SK04GTX View Post
Go online to Advance Auto and use coupon code TRT30 for 30% off and a speed sensor is $21 (order online, P/U at store). Both are the same part number so just buy one and first put it in the rear (output) to begin. If no change move it to the front (input).
I'm buying mopar
Jrboarder27 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.