Jeep sputtering when cold -
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 > Models > Jeep Wrangler Forums > YJ Wrangler Technical Forum > Jeep sputtering when cold

SPARTAN LOCKERS are on sale BIG TIME at ROCKRIDGE 4WD!FS: Jeep Fog Light LED Bulbs! Several Brightness Options! Yukon Ultimate 35 axle kit for c/clip axles with Yukon Zip

Unread 02-05-2002, 03:01 PM   #1
Registered User
Join Date: Feb 2002
Location: Georgia
Posts: 1
Jeep sputtering when cold

Hello all,
My 88 Wrangler 4.2 has a problem. When engine is cold, I get really bad sputtering at about 2k rpm, and black smoke coming out of the exhaust.

When engine warms up, problem goes away, and engine runs fine.

I figured this is carb related, but could it be the O2 sensor also? The carb is brand new, but could something be holding the choke in the wrong position? I just finished giving the engine a full tune-up.


88 Wrangler 4.2 5spd
33X11.50's, 3" lift.
Many exterior mods..
FishWagon is offline   Reply With Quote
Unread 02-05-2002, 04:26 PM   #2
Bob K
Registered User
Join Date: Nov 2001
Location: New Bedford, MA
Posts: 987
Yes, sounds like the choke is running too rich during warm-up. If the coil spring is not adjustable you might be able to adjust it by bending the arm. I recommend the JuiceBox ignition system to anyone with a pre-'91 YJ or CJ. Best $130 you could ever spend on your Jeep.
'87 Wrangler YJ 4.2 I6 (sorry, sold)
JuiceBox ignition
2 1/2" ProComp Lift
31" BFG A/T's
K&N Filter
Custom Rock Guards
Turbo Muffler
Rear Track Bar in the shed
Other Tricks I won't tell to just anybody!

'99 Grand Cherokee 4.7 V8
Towing Package
ProComp MX6 shocks
Borla Exhaust
Tow Hooks
Alpine CD with Infinity+iPod connect
Just getting started!

If you're not living on the edge...
you're taking up too much space.
Bob K is offline   Reply With Quote
Unread 02-05-2002, 10:49 PM   #3
Registered User
Join Date: Dec 2001
Location: New York
Posts: 27
I have the same problem with MY 89 YJ. I was thinking about the juicebox. Do you happen to have a picture of it? Are there different models that i should be aware of?? Any advice would be great.
Johnny'sJeepen is offline   Reply With Quote
Thread Tools

Suggested Threads

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