Someone please help
 

Hey guys im new to the site and any info would be greatly appreciated. I have an 04 5.9 and I am having problems with lag and shifting through every gear. When I get on the Highway and give it gas it seems to lag and will not go over 1800 rpms when I let off the gas it shifts to the next gear and does the same thing. Also the boost will not go over 17 pounds when before I was hitting 30 could this be from one thing or could i have multiple problems with this truck. Also a few weeks back i threw a code. A friend of mine put a scanner on it and said it was the injector harness. Anyone who can help please do im open to suggestion. Thanks Guys

sounds like a boost leak to me man. hope ya figure it out :U:

The CEL on right now?? Could be that it's in limp mode. Double check and see if the code didn't come back.

it has not come back on since it was cleared

Jay, if you can wait a few months I'll fix it for ya, maybe some new injectors, gauges, etc :w2: :pca1:

That sounds to me like limp mode. Clearing the code and not fixing the problem aren't the same thing which I'm sure you already know.

However, your truck, the 2004 Dodge is generally pretty trouble free so this is likely something simple.

Because you have a Juice you don't know what your fuel pressure is. I would get that tested with a manual gauge on your CP3 injection pump. Next, get a scanner or a smarty box to tell you about the code. Research it here and determine if it can be fixed or what else it might be. If you said injector harness, I would inspect to make sure it hasn't rubbed itself bare, inspect that it is grounded correctly and inspect that it is still connected to all the leads on the injectors themselves.

Assuming all that is fine, it is likely you have a bad #4 or #6 injector. For some reason these are the ones that go. I don't know why. Get some stage2 or 3 aftermarket ones instead of screwing around with these OEM crap sticks. Check the sponsors for those. Leak down tests and pop tests are $$ and unless you have warranty not really worth it if you ask me.

Assuming that checks out fine, inspect your wastegate, your turbo itself and the boost fittings into the intercooler. If I remember the 2004 may have the plastic ends on the intercooler. These crack with boost over 40 pounds. On an otherwise stock truck that's nearly impossible to do though.

Also just for kicks you may want to inspect your MAP and IAT sensors. Pull and clean then. You can also remove and drive your truck stock for a bit and see if that does anything.

There is a number of things it could be but mostly it is fuel related.