misfire

  1. A

    1998 wrangler TJ 4.0: spit, sputter, backfire.

    1998 wrangler 4.0 Misses like crazy upon start up. Kinda levels out a little bit while idling. Rev it up around 2k or so and it back fires and pops like crazy. New distributor & cap/rotor. New wires. Plugs are gapped. Fuel is at 49psi and holds. I have spark from the coil. I read that on of...
  2. S

    Misfire on cold start

    2004 Jeep Wrangler 4.0 Hello guys, first time ever posting in a forum so I'll jump right into the issue. In the past week it's been below 0° in the mornings, when I start my jeep on the cold mornings I get a misfire out of cylinder 2 and 3, once the engine warms up it seems to run fine, maybe a...
  3. MoonShadowTJ

    TJ seems to burn through coil packs

    My ‘01 TJ Sport 4.0 seems to burn thru Coil Packs lately. My TJ started rough idle after start following a 20+ minute stop after warming up and NO codes. Usually it would smooth out and drive great. Cold startups were perfect. One thing of interest is the 4.0 engine runs very hot. The hood...
  4. digitalerik

    Error code P0171 and less aceleration power

    Some ideas of P0171 specificlly with less power at acelerate, just a little bit, like a missfire. This issue is intermitente until now, but if something need maintenance I want to prevent any bigger issue. My mechanic will do in 2 more days maintenance to injectors and all throttle body...
  5. Lorenzo Altarocca

    Misfire with no codes

    Hi from Rome, Italy where I converted my 1999 Jeep Wrangler 4.0L in a LPG powered to pass emission restrictions here and run everyday as a daily driver in city centre. I decided to make this post cause I can't really figured out the problem after many attemps. Symptoms are some little random...
  6. 1Blacktj

    A place to start on wiring issue

    So this morning, my Jeep started misfiring like crazy and had the check engine light start flashing. When I got it back home, I went to check the code and the obd2 would not connect to my scanner as well as the "no bus" code on the odometer. I have had to park my Jeep in the grass the last few...
  7. TJFett01

    P0201: How would you recommend repairing these wires?

    Engine has been running slightly rough, audible random misfiring (no misfire codes), slight shaking of the vehicle and P0201 was tripped. Inspected the wiring on injector 1 and found exposed wires. Further inspection of other electrical connections (other 5 fuel injectors) look similar with...
  8. Zach O'Neill

    Random Stall / Misfire

    Firstly apologies, I’ve posted quite a bit about this in the past but I’m at a loss and don’t really know what else to do. So here I am again , I’ve had some major issues with my 2004 4.0 Auto TJ that I’ve posted extensively about and had some really helpful conversations about , but...
  9. Actormike

    Replace valves for cylinder 1 for misfire at idle or low speed only

    Recently we had a water pump replaced on a 2004 Jeep 4.0L The next day it started misfiring on Cylinder 1. The engine never overheated and two shops agree there are no signs it overheated. The new shop is telling is the below and provided the video/photos. Misfire is not present under load at...
  10. Jakob McElhaney

    Jeep TJ misfiring when warm

    Looking for help again with my 97 Jeep TJ 4.0. Within the last 300 miles, I’ve replaced the exhaust manifold, plugs, wires, distributor cap, ignition coil, upstream o2 sensor, and also went and done the heat shield on the exhaust manifold, fuel rail and injectors. I’ve been chasing a battle of a...
  11. Cyclopscop

    Cylinder 3 misfire

    While on my way home from 150 mile trip, I stopped to fuel. When I started the Jeep it gave a check engine light, code reader said (cylinder 3 misfire), for context it was a mostly interstate drive, and I had been driving approximately 65- 75. It’s a 04 with inline six. I had the plugs replaced...
  12. Tojeepornottojeep

    P0339 & P0300 codes

    I have 2005 tj 4.0 auto keep getting codes p0339 & p0300 I have changed the camshaft and crankshaft sensor, full service change of plugs & oils etc, injector clean and currently have a ignition capacitor on order hoping that would be the weak link. it runs smooth when start up and idling...
  13. M

    Misfiring problem

    I have a 1999 Jeep wrangler Sahara with the 4.0 in it. It started to misfire on me so I replaced all the ignition coil, plugs, and cables (one broke) but it is still missing. I’m doing my own research but hope you guys can help. If I take it on the road it spits and sputters but if I jump on the...
  14. Meatlord

    Late model 4.0 missfire issues discussion

    Back story, I bought an 06 Rubicon 6spd from a local with a misfire issue for a reasonable price. I'm no stranger to jeeps or the 4.0 engine either. 200k miles, look to be all road miles, PO was surprised on the test drive when I got the diff lock lights to come on... This condition exists...
  15. C

    Engine sputtering and misfiring

    Good evening Jeep experts. Jeep rookie here. Was trying to find a thread that was close to my problem. 1998 TJ 4.0. 51k miles. Was miss firing and throwing a misfire code, reset that code, continued with a new code misfire multiple cylinders. Changed all plugs (they were original plugs) with...
  16. racecar825

    P0301 misfire at idle (puffing noise at muffler)

    As the title says, I have a misfire on cylinder 1 at idle. It's a 1998 4.0 with 165k miles. I can feel slight vibrations while in the car and it is idling. I had this code a few months ago and changed the plugs, coil wires, distributor cap, and the distributor rotor and the problem went away...
  17. M

    Confusing misfire

    Hi all, I have 1999 4.0 sport - has run perfectly for years, however recently it has developed a misfire when first driving the car. No issue starting the car but once I get off the drive and take it up the road it pops and bangs and judders until I floor it and it all seems to clear and then...
  18. T

    Help with P0306 misfire code on 2006 Jeep Wrangler 4.0

    2006 Jeep Wrangler X 4.0 6-speed I have the dreaded misfire. The weird thing is it will occasionally go away and then come back. I can tell when it's going to come back because it gets noticeably rougher. I have tried changing out spark plugs, changed the ignition pack, new 4-hole Bosch fuel...
  19. smash_lizard

    Consistent misfire - cylinder 4 only

    2002 2.5L. Headgasket/head rebuilt July 2019. Since wheeling season around here ended in December the jeep has been sitting on its trailer and only been started once in February. At that time there were no issues and it ran normally. This past weekend it was pulled off the trailer in...
  20. wheelnmac

    2000 4.0 TJ misfire issues

    So here is the long version. I was on my way to the desert with my trailer in tow and the Jeep quit on a hill. Got it towed home and replaced the crankshaft position sensor. Nothing. Drained the fuel and replaced the pump. Bingo. Fast forward to last week. The jeep has been sitting. Starting it...