Help with rough idle - 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 > Help with rough idle

Stainless Steel Door Hinge PinsPoly Door Hinge BushingsSteinjager TJ tube doors

Reply
Unread 04-02-2013, 02:07 PM   #1
akagrifty
Registered User
1989 YJ Wrangler 
 
Join Date: Nov 2012
Location: clementon, nj
Posts: 19
Help with rough idle

I have an 89 wrangler with a 4.2 that has a rough idle and at cold starts surges. This started after I replaced the distributor and spark plugs. I didn't replace the cap, rotor, or wires because they were replaced only 5000 miles ago. I checked all the vacuum lines which was not easy. I did the nutter bypass when I rebuilt the engine 5000 miles ago. The carb is brand new also replaced when the engine was rebuilt. I replaced the distributor because the vacuum advance was bad. The ignition module and capacitor were replaced just before the engine was rebuilt. Does anyone have any suggestions because I am out of ideas of what to check and I don't want to pay for something that I could easily check myself?

akagrifty is offline   Reply With Quote
Unread 04-02-2013, 02:24 PM   #2
Old4X
Registered User
1990 CJ7 
 
Join Date: Nov 2008
Location: Ga
Posts: 4,810
Add a dedicated ground to the black wire in the 3 wire bundle coming from the distributor.

Double and triple check your firing order. And change the plugs and wires one at a time to see if you have a bad one or damaged one while working with them.
__________________
Rust free YJ for sale. Need more room in barn.
Old4X is online now   Reply With Quote
Unread 04-02-2013, 03:21 PM   #3
akagrifty
Registered User
1989 YJ Wrangler 
 
Join Date: Nov 2012
Location: clementon, nj
Posts: 19
Yeah I forgot to say that i tried grounding out each plug to see if any one cylinder was getting the misfire but that didn't help at all i would get the 1 cylinder misfire along with the other intermittent misfires on all 6 cylinders. I will try the dedicated ground though thanks.
akagrifty is offline   Reply With Quote
Unread 04-02-2013, 03:54 PM   #4
Que89YJ
Web Wheeler
1989 YJ Wrangler 
 
Join Date: Apr 2008
Location: Detroit, Michigan
Posts: 14,806
If it is nuttered the you need to add the dedicated distributor ground Old 4x suggested.
Que89YJ is offline   Reply With Quote
Unread 04-02-2013, 04:11 PM   #5
akagrifty
Registered User
1989 YJ Wrangler 
 
Join Date: Nov 2012
Location: clementon, nj
Posts: 19
ok I added the ground wire and that did nothing. Let me make sure I understood what you meant. I took the black wire from the distributor cut it. Then I spliced those 2 wires with a new wire and ran the new wire to the ground side of the battery.
akagrifty 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.