User Tag List

Page 1 of 2 12 LastLast
Results 1 to 10 of 14

Thread: 2006 TJ 4.0 Rough Idle

  1. #1
    Wheelin requires wrenchin Doppler's Avatar
    Join Date
    Jan 2010
    Location
    Newcastle
    Posts
    2,695

    Branch
    Air Force
    Status
    Retired
    Served
    1990 to 2010

    Closest Installation

    Tinker AFB
    Mentioned
    9 Post(s)
    Tagged
    0 Thread(s)

    Default 2006 TJ 4.0 Rough Idle

    Just looking for some inputs from people familiar with the 2006 ignition system. Went under the hood looking at what was needed to give this thing a tune up and noticed the distibutor cap isn't really a distributor cap. From what I can tell it looks like it would only contain an electronic module for firing the three coils. Anybody done any work on their's? Mine has developed a rough idle, so before I just go out and buy new plugs and wires I thought I'd ask if any part of the distributor needs to be changed on these newer models. My last Jeep was an 88 XJ and I new that thing inside and out, still learning about my TJ. Thanks!

  2. #2
    Land Squid Jeffb_79's Avatar
    Join Date
    May 2008
    Location
    Fairfax, VA
    Posts
    3,593

    Branch
    Navy
    Status
    Served
    Served
    1999 to 2010

    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)

    Default

    No distributor, and no wires in an 06.
    How many miles on it? First thing I would do is change the plugs.
    What do you mean by rough idle? Is it fluctuating a few hundred rpms, or is it trying to throw you off the seat?

  3. #3
    Mountain Valley Customs
    Join Date
    Jun 2008
    Location
    Millmont
    Posts
    1,438

    Branch
    Air Force
    Status
    Served
    Served
    1996 to 2005

    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)

    Default

    Your jeep has what's called DIS (distributorless ignition system). Those long coil packs very rarely go bad, but like anything else, it can happen. You also don't have plug wires since the ignition system is considered "coil near plug". More than likely you have a fouled plug as a result of some bad gas or dirt in the gas. To change the plugs, you need to remove the (3) 13mm retaining bolts on the coil pack, slide the safety clip to the side and unplug the electronic connector at the end nearest the firewall. Then the coil pack, along with the 6 boots will lift off.

    Is you jeep throwing any codes?
    Mountain Valley Customs www.mvcustoms.com 570.217.7284
    Specializing in 4x4s and custom fabrication


  4. #4
    Wheelin requires wrenchin Doppler's Avatar
    Join Date
    Jan 2010
    Location
    Newcastle
    Posts
    2,695

    Branch
    Air Force
    Status
    Retired
    Served
    1990 to 2010

    Closest Installation

    Tinker AFB
    Mentioned
    9 Post(s)
    Tagged
    0 Thread(s)

    Default

    Quote Originally Posted by Jeffb_79 View Post
    No distributor, and no wires in an 06.
    How many miles on it? First thing I would do is change the plugs.
    What do you mean by rough idle? Is it fluctuating a few hundred rpms, or is it trying to throw you off the seat?
    The idle will drop off a few hundred RPM's, kind of like an old carb stutter. then jump back up. At idle it's running around 600 rpm, figure it should be up around at least 800.

  5. #5
    Wheelin requires wrenchin Doppler's Avatar
    Join Date
    Jan 2010
    Location
    Newcastle
    Posts
    2,695

    Branch
    Air Force
    Status
    Retired
    Served
    1990 to 2010

    Closest Installation

    Tinker AFB
    Mentioned
    9 Post(s)
    Tagged
    0 Thread(s)

    Default

    Quote Originally Posted by crazy4ink View Post
    Your jeep has what's called DIS (distributorless ignition system).

    Is you jeep throwing any codes?

    No codes.

  6. #6
    Land Squid Jeffb_79's Avatar
    Join Date
    May 2008
    Location
    Fairfax, VA
    Posts
    3,593

    Branch
    Navy
    Status
    Served
    Served
    1999 to 2010

    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)

    Default

    I think plugs have a 30k mile life (I could be wrong). So might not be a bad idea to change them anyways if you're over that limit.
    A dirty IAC can cause idle fluctuations and low idle...

    The idle air controller is what meters air into the engine through the throttle body when the engine is at idle RPMs when the butterfly valve is closed (which is closed whenever your foot is off the accelerator pedal).

    It's held onto the throttle body via two T-25 bolts on the engine-side of the throttle body. I don't doubt the Chilton's manual doesn't cover it well, I consider Chilton's and Hayne's manuals little better than nothing.

    Remove the IAC via those two screws and then clean its solenoid actuated plunger gently with aerosol throttle body cleaner and a toothbrush. Use a small brush like a baby bottle brush to also clean the oriface (opening) the plunger fits into which is how the air gets into the throttle body. If either is dirty, air can have trouble getting into the engine when the engine is idling.

  7. #7
    That Guy afjeep's Avatar
    Join Date
    Jan 2008
    Location
    Valdosta
    Posts
    3,587

    Branch
    Air Force
    Status
    Serving
    Served
    2004 to Present

    Closest Installation

    Moody AFB
    Mentioned
    15 Post(s)
    Tagged
    0 Thread(s)

    Default

    that electronic cap on what is normally your distributor is, i believe, your camshaft position sensor. the shaft it is on is, once again, i believe, your camshaft syncro. as for your rough idle, i'd def start with the simplest and cheapest fix first. plugs, then move to the more expensive ones.
    2004 Rubi, Poison Spyder Bumper with Trail Stinger. Warn M8000 winch, Rock Krawler X-factor long arm 4 inch lift, 35x12.50x15 BFG KM2s on Procomp 8 inch steelies, Tom Woods Driveshaft, Poison Syder Full Roll Cage, Tuff Designs rear bumper/Tire carrier, MetalCloak Arched Tube Fenders with 6 Inch Flares, Flowmaster Hushpower Muffler, Vanco Big Disk Brake upgrade, Line-X'd tub and cage.

  8. #8
    Wheelin requires wrenchin Doppler's Avatar
    Join Date
    Jan 2010
    Location
    Newcastle
    Posts
    2,695

    Branch
    Air Force
    Status
    Retired
    Served
    1990 to 2010

    Closest Installation

    Tinker AFB
    Mentioned
    9 Post(s)
    Tagged
    0 Thread(s)

    Default

    Sorry, 39,000 miles.

  9. #9
    Wheelin requires wrenchin Doppler's Avatar
    Join Date
    Jan 2010
    Location
    Newcastle
    Posts
    2,695

    Branch
    Air Force
    Status
    Retired
    Served
    1990 to 2010

    Closest Installation

    Tinker AFB
    Mentioned
    9 Post(s)
    Tagged
    0 Thread(s)

    Default

    I've also heard reports of the spark plug boots arching through to ground not getting full spark to the plugs. Has anyone experienced this or do you know if the boots can be bought seperately from the coils?
    Last edited by Doppler; 03-30-2010 at 21:47.

  10. #10
    Land Squid Jeffb_79's Avatar
    Join Date
    May 2008
    Location
    Fairfax, VA
    Posts
    3,593

    Branch
    Navy
    Status
    Served
    Served
    1999 to 2010

    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)

    Default

    The coil pack is a single unit. The dirty IAC is a fairly common issue though.

Page 1 of 2 12 LastLast

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  
Get the MJ Supporter Membership for a little less than $0.06 a day and get more space, 2 MJ Stickers and no banners ads. [Check it out]