Hey guys i'm new to the forum and have a question for you. I have an 03 4.7L dodge ram. My check engine light came on and gave a p0300 code for a random misfire. It comes on for 3 or 4 days and goes off for a day or two then comes back on. I have replaced spark plugs and coil packs, anybody heard of this problem before?

 

I have the same issue. I have also replaced my coil pack and plugs. had another guy tell me it might be lack of fuel pressure. and to change the fuel filters. which sucks becuase they are inside the tank. I have and 02 4.7l. engine only has 80,000 but the rest of the truck is at 206,000. I guess i will see what some say to your post. was about to post my own.

my isssues are a few months back 2 and 7 misfire. (replaced all plugs and 2 pack) then 4 and 6 mifired replaced those packs. well now i'm back too cyl 2 and 7 again misfiring. I have an evap leak small and large. not sure what those are.

 

I've heard the same thing about the fuel pressure; i've also heard possible bad fuel injector but the code is always the p0300 random misfire so i'd think it would give me a specific cylinder if it was a bad injector, also it has never been misfiring that i'm aware of it has never sounded bad, the only thing i have noticed is when the check engine light is off it seems to have a little more pep in the motor at take off. I'm stumped

 

my grandfather has an 02 4.7 that is now in the shop for the same thing, the CEL came on he said it has been harder to start when cold lately but otherwise runs fine etc. The dealer told him bad injector but considering he is cheap as can be would not surprise me if he got bad fuel either...

 

the evap codes can be fixed by climbing under the drivers side of truck just in front of the gas tank there is a container with rubber hoses running into it one of them is cracked or split easy fix

 

A friend of mine had a P300 on her 02 Ram and it was definitely missing bad. She got a full tune up and it runs great now.