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Unread 09-16-2013, 08:31 PM   #1
Registered User
2003 WJ 
Join Date: Jun 2011
Location: milton, ny
Posts: 75
help jeep misfiring!

So my jeep was running rough, 03 4.7 130 k on it and I was thinking maybe it was just a bad batch of gas because I just filled up this morning then it got worse and now I'm throwing a p0302 cylinder 2 misfire idk what to do my plugs are recent maybe 10 k ago replaces with champion platinum I believe.. And advice? Do you think that it could be a bad tank of gas?

2003 4.7 quadratrac II 120k bone stock for now :)
Dana 30/186MM Front Axle
3.73 Rear Axle Ratio
Dana 44/226MM Rear Axle
kharney is offline   Reply With Quote Quick reply to this message
Unread 09-17-2013, 01:46 AM   #2
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2000 WJ 
Join Date: Sep 2012
Location: Rocklin, California
Posts: 705
Clean your iac. Plenty of threads on that. Also YouTube videos. See if that helps.

There might be a way to do a homemade smoke test to check for a vacuum leak.

Could be a lot of things though, search function on the forum is a huge help in these cases.
doorjamm is offline   Reply With Quote Quick reply to this message
Unread 09-17-2013, 02:58 AM   #3
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1999 WJ 
Join Date: Jul 2011
Location: Las Vegas, NV
Posts: 153
Double check your plug to make sure it's not fouled. Swap the #2 coil with a coil from another cylinder. Clear your codes. If the code jumps to the cylinder you swapped coils with, your coil could be bad.
1999 WJ 4.7, 242HD, IRO 4" Long Arm, IRO Adj Track Bar, JKS BPE, JKS Quick Disco, 15" Cragar D-Window, 32" BFG KM2, V3 Projectors, DDM Tuning 55w 5k HIDs
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Unread 09-17-2013, 09:06 AM   #4
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Join Date: Dec 2008
Location: oakville, canada
Posts: 817
have you ever overheated? If its not a spark or fuel issue it can be a loose valve seat, when it happens usually on #2 cylinder
oldfamilyguy is offline   Reply With Quote Quick reply to this message

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