Help, error code 300 -
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Unread 08-20-2006, 02:42 PM   #1
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2007 JK Wrangler 
Join Date: May 2006
Posts: 333
Help, error code 300

Every once in a while I get the "check engine" light during a long trip or wheeling, it normally goes away after a few days.
I got it today again, did the whole diagnostics thing and it came up with 2 error codes:

300: Misfire detected in multiple cylinders, and
304: Misfire detected in cylinder #4

What could cause these misfires? Is it a major concern?

There are two types of pedestrians, the quick and the dead.
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Unread 08-20-2006, 02:48 PM   #2
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Join Date: Nov 2005
Location: Colorado Springs
Posts: 471
I had the same problem for over a year while I was running 32" tires with 3:07 gears. The problem hasn't re-occurred since I regeared.

I think constantly lugging the engine fouled the plugs.

My .02
'01 TJ. 4"Full Traction. 1" BL/MML. 35" BFG Muds. ARB's front & Rear. Full skids. Warn Winch. Lots of other crap!
ocezam is offline   Reply With Quote Quick reply to this message

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