post #1 of Old 10-24-2013, 08:36 AM Thread Starter
Futuramic76
Registered User
 
Join Date: Sep 2013
Posts: 7
1999 Jeep Grand Cherokee, 375, 000 mi.

Great car, original owner, freq.oil changes.

Replaced my Crank sensor, alternator, MAP sensor. Engine is sputtering on warm start ups until I get on freeway. Gas mileage is down by 40%.
Fuel injectors?
Cam shaft sensor?
Spark plugs?
Vacuum leak?

Likely issue?

Futuramic76 is offline  
post #2 of Old 11-01-2013, 07:11 PM
uberxj92
Registered User
1992 XJ Cherokee 
 
Join Date: Oct 2012
Location: umatilla
Posts: 1,961
Wow. That's a beast. Got to live it. That's a hefty fuel drop. When was the last tune up? With ethanol you get half life on tune ups nowadays.
Check engine light on?
Could be o2 sensor.
Which engine do you have?
That many miles you may want reward her with a rebuild.

http://www.jeepforum.com/forum/f177/92-xj-sadness-2075657/index2.html
uberxj92 is offline  
post #3 of Old 11-01-2013, 07:25 PM Thread Starter
Futuramic76
Registered User
 
Join Date: Sep 2013
Posts: 7
Just replaced M.A.P. sensor, O2 sensor, fuel injector cleaner.
Think maybe a vacuum leak?
Futuramic76 is offline  
post #4 of Old 11-01-2013, 07:26 PM Thread Starter
Futuramic76
Registered User
 
Join Date: Sep 2013
Posts: 7
4.7 L all-wheel.
Futuramic76 is offline  
post #5 of Old 11-02-2013, 03:42 AM
uberxj92
Registered User
1992 XJ Cherokee 
 
Join Date: Oct 2012
Location: umatilla
Posts: 1,961
Sounds vacuum. That's a lot if mikes on that particular engine. I'm impressed. Keep her up

http://www.jeepforum.com/forum/f177/92-xj-sadness-2075657/index2.html
uberxj92 is offline  
post #6 of Old 11-02-2013, 05:17 AM
Duh
Registered User
 
Join Date: Apr 2002
Posts: 491
I wouldnt rule out a sticking injector. Stuck open it will give a stuttering appearance at times when there is too much fuel and not enough air-think about stoichiometry.
Duh is offline  
post #7 of Old 11-03-2013, 04:01 PM Thread Starter
Futuramic76
Registered User
 
Join Date: Sep 2013
Posts: 7
Thank you guys. I will explore those solutions.
Futuramic76 is offline  
Reply


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



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