4.0 problems - 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 Wrangler Forums > YJ Wrangler Technical Forum > 4.0 problems

Smittybilt Products at Oconee Off-Road!Building a Bumper?Ruffstuff Axle Simple Swap Kit!

Reply
Unread 07-12-2010, 05:35 PM   #1
taterkins02
Registered User
1992 YJ Wrangler 
 
Join Date: Aug 2008
Location: Mercersburg
Posts: 22
4.0 problems

my 93 wrangler 4.0, it idles fine, you can rev the guts out of it while its sitting there, but when you go down the road and the engine gets warmer it gets a hesitation then it loses power. what could be the problem? could it be the cps? and if so is there a way you can test them?

taterkins02 is offline   Reply With Quote
Unread 07-12-2010, 05:38 PM   #2
clush
Registered User
1994 YJ Wrangler 
 
Join Date: Jul 2009
Location: Lexington, Kentucky
Posts: 254
must be a common issue. mine is similar, and it has gotten worse over time.
clush is offline   Reply With Quote
Unread 07-12-2010, 05:40 PM   #3
laybackman
Bikini Bridge Inspector
 
laybackman's Avatar
1995 YJ Wrangler 
 
Join Date: Dec 2002
Location: Massachusetts
Posts: 6,012
Quote:
Originally Posted by taterkins02 View Post
my 93 wrangler 4.0, it idles fine, you can rev the guts out of it while its sitting there, but when you go down the road and the engine gets warmer it gets a hesitation then it loses power. what could be the problem? could it be the cps? and if so is there a way you can test them?
How old is the cat converter? When they start to go bad they will begin to hurt high end peformance and then it just keeps getting worrse until it starts to literally choke an engine off when it gets hot. It gets progressively worse over time.
__________________
Chicks dig me.....Fish fear me

Getting older, I have developed some special skills. I have the ability to cough, sneeze, fart and pee at the same time.

"If we cannot afford to take care of Veterans, then we should stop making them."
David C. Wilker Jr. USAF (RET)
laybackman is offline   Reply With Quote
Unread 07-12-2010, 05:43 PM   #4
taterkins02
Registered User
1992 YJ Wrangler 
 
Join Date: Aug 2008
Location: Mercersburg
Posts: 22
its a hollow cat. i changed out the tps and map, and still does it, so theyre not the problem.
taterkins02 is offline   Reply With Quote
Unread 07-12-2010, 06:32 PM   #5
idaholtby
Registered User
1991 YJ Wrangler 
 
Join Date: Apr 2008
Location: Meridian, Idaho
Posts: 2,554
Check your fuel pressure at the rail and report back.
idaholtby is offline   Reply With Quote
Unread 07-12-2010, 06:32 PM   #6
Roadyy
Registered User
 
Roadyy's Avatar
1994 YJ Wrangler 
 
Join Date: Mar 2010
Location: Down South
Posts: 1,592
When was the last time the fuel filter was changed?
Have you checked for codes?
You mite want to pick up a fuel pressure gauge and run it to the inside so you can monitor it while driving to see what the psi is when it starts acting up.
Roadyy is offline   Reply With Quote
Unread 07-12-2010, 07:09 PM   #7
idaholtby
Registered User
1991 YJ Wrangler 
 
Join Date: Apr 2008
Location: Meridian, Idaho
Posts: 2,554
Quote:
Originally Posted by UABYJ94 View Post
When was the last time the fuel filter was changed?
Have you checked for codes?
You mite want to pick up a fuel pressure gauge and run it to the inside so you can monitor it while driving to see what the psi is when it starts acting up.
Like he said ^^^
idaholtby is offline   Reply With Quote
Unread 07-12-2010, 08:16 PM   #8
laybackman
Bikini Bridge Inspector
 
laybackman's Avatar
1995 YJ Wrangler 
 
Join Date: Dec 2002
Location: Massachusetts
Posts: 6,012
Quote:
Originally Posted by taterkins02 View Post
its a hollow cat. i changed out the tps and map, and still does it, so theyre not the problem.
When you changed the sensors did you dump the learned memory in the ECM? I would have.
__________________
Chicks dig me.....Fish fear me

Getting older, I have developed some special skills. I have the ability to cough, sneeze, fart and pee at the same time.

"If we cannot afford to take care of Veterans, then we should stop making them."
David C. Wilker Jr. USAF (RET)
laybackman is offline   Reply With Quote
Reply
Thread Tools


Suggested Threads





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.