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Brad, Jeep Dealership Tech
Category: Jeep
Satisfied Customers: 7845
Experience:  19 Yrs Chrysler/Dodge/Jeep. ASE Master (L-1) Certified
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2006: 2006 Jeep v 8 grand cherokee.....have an engine light

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2006 Jeep v 8 grand cherokee.....have an engine light code of p 300......I realize this can be plugs, gas filter, coil, coil or injector.....what do you reccomend first....80k miles...not sure if the gas filter has ever been changed
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I'm a 15 Yr Jeep dealership technician and the P0300 is a Multiple cylinder misfire. Do you have the 4.7 engine? Yes it could be the spark plugs or fuel issue.. Is the P0300 the only code you have? Do you feel it skipping?

Customer: replied 3 years ago.


yes 4.7....
it stalls once and while but nothing in a pattern....not skipping at actually runs great.....just replaced Cellanoid in transmission....


Thanks for the reply!!

Ok since it doesn't skip all the time then it sounds like the P0300 was a stored code.. Which means the issue that was causing it to skip isn't there anymore and there's a good chance that you won't be able to find the problem.. I would start by checking the spark plugs and see if the gap is excessive and if so replace them.. If the plug gap is good then it could be trash in the fuel at one point or the actual pump psi was low at sometime.. If it was skipping right now we could trace down which cylinder was causing the problems but since it's running good then it problem isn't there anymore...

Check the spark plugs is you haven't had a tune-up in a while and then if it skips again check the fuel psi with a fuel psi gauge.. Spec is around 49psi+\-.

I hope this helps, and if you need anymore assistance don't hesistate to ask
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