Hey all, I was wanting to get some suggestions on this check engine light. Its been on for who knows how long, well before I owned the jeep.

Its giving me a P0300, random/multiple misfire code. Along with that a few times (twice to be exact) I have shut the engine off waited about 15 minutes and started it back up to find it stuttering and misfiring pretty badly. But the light was on well before that, during normal driving and with out the obvious running like crap.

It also seems like the gas mileage is low for the city side. When my dad drove the jeep down to me, it was all on the highway for about 220 miles through the mountains up and down hills (up 287 for those of you in CO) and I drove it another 80 miles in the city all on one tank. It got 21mpg.

But now that I am driving it daily in the city its dropped down to 16mpg on the last tank and now its looking like I will be lucky to get 14mpg on this one.

Any one have any similar problems or suggestions?

PS: its all stock except for a 2 inch budget boost and 30 inch tires.

 

First thing I test for a P0300 (random misfire) is fuel pressure. For a 2001, you should have 49 psi, plus or minus 5 psi.

Start there. You have to rule it in or out before moving onto more complex possibilities.

If you don't have a fuel pressure gauge, many parts stores will rent you one inexpensively.

Good luck!

 

Awesome thanks, I will start there.