I had issues this past weekend with a long highway trip with my 2004 Unlimited LJ. It has the inline 4.0 six cylinder. Check engine light came on after about three hours of highway speed driving and 90 degree weather. Once I got to my destination, and the Jeep cooled down ( not any temperature issues ), it started right up and seem to be fine. Drive home on Sunday, same issues with loss of power. Check engine light has been on the whole time as I had not gone anywhere to read the codes and reset.
Anyway, after stopping in my auto parts shop and reading the codes - P0300, P0301, P0304, P0306. Reset and light is off - couple of short trip near the house and no issues or light coming back on. I remember this on my other LJ, and think it has to do with plug wires and or heat shielding. Can I get any suggestions or remedies? The codes are cylinder misfires. Thanks, Phil
Anyway, after stopping in my auto parts shop and reading the codes - P0300, P0301, P0304, P0306. Reset and light is off - couple of short trip near the house and no issues or light coming back on. I remember this on my other LJ, and think it has to do with plug wires and or heat shielding. Can I get any suggestions or remedies? The codes are cylinder misfires. Thanks, Phil
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