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Very weird misfire - stumped/help please..

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Old Jul 20, 2011 | 03:07 PM
  #46  
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Just thought id jump in real quick and say that's its 95 out right down and I've been drive around town(stop and go, nothing over 30/35 cause of traf) and the light has not come on. Althought it came on when I was going to practice today, when it was 76 out. (7am)

Edit: I'll read and post back when I get home, I can only do so much at stop lights hahahah

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Old Jul 20, 2011 | 05:04 PM
  #47  
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http://www.go.jeep-xj.info/HowtoCPSchange.htm

SO should I do this and go from there?

http://www.autopartswarehouse.com/sk...gs+Best+Seller

Last edited by Zack92MJ; Jul 20, 2011 at 05:13 PM.
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Old Jul 27, 2011 | 10:17 PM
  #48  
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Any ideas?

Anyone?

And now my trans mounts are rattling!
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Old Aug 3, 2011 | 09:13 PM
  #49  
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Well Ive taken it two different shops and no one can figure it out?
Does anyone have any ideas? Anyone? lol It could be your grandma for all I care, I just need some ideas on where to go next
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Old Aug 3, 2011 | 10:26 PM
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Did you do a breakdown and compression test yet?
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Old Aug 3, 2011 | 10:55 PM
  #51  
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Let me answer that with a question..hahah how do even do either of those? Lol

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Old Aug 3, 2011 | 11:32 PM
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Arghhh your best bet would be Google it. You know what the compression test does. The psi doesn't matter as much as how even it is cylinder to cylinder. The leakdown test will tell you where if anywhere you're losing compression from. Also a vacuum test. Google the procedures for these I'm sure you will get step by step instructions.
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Old Aug 17, 2011 | 04:43 PM
  #53  
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Well I installed new neon injectors and my light was gone for more than a day..but it came back on at 41 miles

I haven't pulled the codes yet but one can assume its a miss on 1 & 2
Attached Thumbnails Very weird misfire - stumped/help please..-forumrunner_20110817_174104.jpg  
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Old Sep 25, 2011 | 05:53 AM
  #54  
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It sounds to me like you have the same issue i did with my xj it runs great until she heats up and you shut it off. The problem starts on restart after a heatsoak or even sometimes sitting at an idle when its hot and arent driving helping move some air. Pretty sure its in the #3 injector and theres a few posts about it not sure of the size (mm) insulator you will need but the injector is way to close to the exhaust and causes the fuel to evaporate before it can fire that cylinder. So get some kind of heat protector on the injector and im almost sure your problem will be fixed!! i would just wrap them all to insure none are getting too hot. happy jeepin hope thats what your issue is.
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Old Sep 25, 2011 | 05:18 PM
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Originally Posted by braylens dad
It sounds to me like you have the same issue i did with my xj it runs great until she heats up and you shut it off. The problem starts on restart after a heatsoak or even sometimes sitting at an idle when its hot and arent driving helping move some air. Pretty sure its in the #3 injector and theres a few posts about it not sure of the size (mm) insulator you will need but the injector is way to close to the exhaust and causes the fuel to evaporate before it can fire that cylinder. So get some kind of heat protector on the injector and im almost sure your problem will be fixed!! i would just wrap them all to insure none are getting too hot. happy jeepin hope thats what your issue is.
My misfire is one 1 & 2 . I think I grabbed the wrong kind of spark plug. Because when I put them in I went 6 to 1 ..and 1&2 would have been a different box than 3&4 and 5&6
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Old Oct 7, 2011 | 08:45 PM
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Well turns put I got the right spark plugs...but I got a new set and regapped one of the old ones...so I put the new one in two and the newly gapped one in one. Missfire is gone out of two. And I'm planning on putting in my other new one in one tomorrow.
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