misfire

  1. JeepGirl1013

    Misfire made worse

    I bought a fuel pump from dead jeep a while back and after a few months I needed to prime the pump to get her to start. Figured the regulator was going out. Dropped the tank and replaced the regulator only. Also changed spark plugs they were showing discoloration on one side and had some bluing...
  2. F

    P0201 intermittent help & advice

    Hey all, I have an 02 Jeep TJ automatic giving me some trouble for a few months. Started about 2-3 months ago when I randomly felt stuttering/misfiring-ish when coming to a stop at a light or stop sign, and it would remain as I initially hit the gas to get going again until I got the speed up...
  3. Hmr

    Throttle Body Replacement?

    Need some advice: Just bought a 1997 TJ! It ran great for about two weeks, then popped a code (P0302) ran fine for about a week after that then on my way back from the gym it started dying when under any load and producing a high idle. Took it to the shop the next morning and they told me no...
  4. Nick Mitty

    4.0 - Low RPM Misfiring Issues

    Hello Everyone, I am currently experiencing a misfire issue on my TJ. I have read through the other similar threads here to begin diagnosing and fixing the issue, but with no luck so far. So I have decided to outline my issue as best I can below. Jeep Information: 2006 Jeep Wrangler TJ Sport /...
  5. LostintheForest

    High Idle Solved

    I have been chasing a high idle for a while, I had also had a very difficult cold start but that was solved with an IAC. I thought I fixed the old one, but it fell apart again. Doesn’t stall at cold start now, but still had a hanging idle/ high idle most of the time. If I pulled the throttle...
  6. H

    Difficult P0300 Misfiring Issue

    Hey gang, I'm at my wits end, mostly cuz I'm scared of what's happening to my dream Wrangler. Sorry if this post seems long but I want to provide as much details as possible so hopefully someone can point me in the right direction. So here is a little backstory and info: About 5 months ago, I...
  7. G

    98 TJ 4.0 intermittent misfire, no codes

    I'll be driving along with the engine hot and it misfires under steady throttle causing the whole car to jolt. The tach needle drops a few hundred and then shoots right back but there are never any codes. This problem has been happening over the past couple of years, it'll misfire here and...
  8. K

    Misfire and hesitation

    Hey all! I have a 1997 TJ 5sp manual 4.0L I just replaced pistons, piston rings, some bearings, and gaskets all around (except the oil pan gasket). this project took way too long and I was getting excited to have her back on the road. after putting everything together and getting her running and...
  9. Jcrubicon

    Idle misfire that has been haunting me

    Ok I have a 2006 Rubicon 6 speed with an intermittent misfire issue that I’ve been chasing for over a year. I’ve lost lots of money and sleep over this one and I can’t find an end in sight. The jeep will run perfectly all day long and then once you put the engine under heavy load ex. (Flooring...
  10. Matt14

    Troubleshooting small sounding misfire with P0301, P0431, & P0123 codes

    This started after an off-road trip on the way back had a really bad misfire in cylinder one. So bad I had to end up towing it home. Ended up replacing the spark plugs, and that fixed it for a while. They were really poorly gaped (i didn’t know gapping was a thing lol). To sure things up I...
  11. 0

    P0175 (Please Read Entire Post, Lots Of Crap Going Into This)

    Have an 05 TJ 4L I6. Had a misfire issue when I bought in 2020, let it run until it started having major problems with the following: acceleration on the highway, idling rough, multiple turns of the key to start. When I first got it, replaced the starter and spark plugs (used autolite plugs like...
  12. jw_LJ

    Another TJ 4.0 Misfire Thread (2005 LJ)

    Hello everybody, I've been visiting the forum for years and have learned so much through this amazing site, and I finally am coming to you guys about an issue I've been having for years now. While I want to provide as much information as possible, I will keep it as brief as possible. I hope you...
  13. TheDWord

    Jeep stalls when stopping after driving distance at high speed

    Long detailed post ahead. Thanks for reading! 2001 TJ automatic, 4.88 gears (relevant for the speed figures below) BACKGROUND: I spent a ton of time late 2021 and half 2022 trying to troubleshoot a misfire issue. Replaced just about every sensor; Mopar replacements where possible, forum...
  14. Kade Saxon

    Computer issue?

    I have a 2004 TJ Rubicon with the 4.0 and automatic (42RLE). About 4 years ago, I was having shifting issues between 1st and 2nd where it felt like a slip/missed the gear, but would only do it once in a blue moon (never threw a code), and would shift into 2nd after about 1-2 seconds of...
  15. tjsahara

    Rough Idle in Gear and Faulty Misfire Codes

    Hello TJ Forum, I have been trouble shooting my 01 TJ with 59k miles for the last year or so and cannot seem to find the cause of its issues. The Jeep has an idle around 500rpm and once put into gear there is an immediate difference in the vibration at stand still; the vibration goes away once...
  16. J

    Misfire on cylinder 1, cylinder 2, and random misfire

    Hello everyone, I have a 1998 Jeep Wrangler 4.0L, I have a check engine light on and it’s giving me the following codes: P0300- multiple/ random cylinder misfire P0301- cylinder 1 misfire P0302- cylinder 2 misfire Anyone know what my issue may be? Been trying to fix this on my days off from...
  17. 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...
  18. 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...
  19. 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...
  20. 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...