Hi there, I'm new to this forum website and I just made an account to see if I can find help or get pointers to solve the problems I'm having with my truck, I got a 2001 Dodge Ram 1500, 5.9 Magnum, 4x4 & Sport package.

For the past month, I've been driving around with a P0304 Code which I initially thought it was a fuel relay control circuit issue, but found it is actually a cylinder 4 misfire. Recently, my truck ended up idling at about 2 grand when I started it cold for 3 or so days and then it would go back to normal afterwards, and as I write this, it's happening again. So I'm confused, has anybody had the same if not similar issues?

Thank you for your time reader,

- Nathan Lykouretzos

 

Two separate problems.

For the high idle, try cleaning the throttle body. Pay special attention to the IAC well.

For the misfire, how old are the plugs??

 

I get what you're saying about the high idle, I was told as well there's a possible crack in my intake manifold, which I think is a secondary possibility considering I have the original engine on the road to 300k miles.

As for my spark plugs, I got them done mid to late summer of 2023. There could be an issue with them but I'm not the most mechanically inclined individual.

I will definitely look into cleaning the throttle body, Lord knows how long it's been since that got cleaned.

 

It may be the plenum issue. Look down the throttle body to the bottom of the intake, If you see oil there it's bad.
http://www.hughesengines.com/Index/p...p?partid=27091

 

Thank you for the link, that'll surely come in handy in due time. I'll take a look once the rain dies down by me, supposed to get rain for the next day and a guy's got work tomorrow. Anyhow though, I know that the 5.9s have a very common issue with plenum gaskets. I can't recall when mine was replaced last unfortunately.