Sounds like I should just bite the bullet and take it to the dealer. The only thing I'm worried about is that I deleted my catalytic converter and replaced the stock muffler with a Donaldson 51" so that gives them an excuse to void my warranty. Also, if they put an in-tank lift pump in it, I don't want to have to mess with that if I ever decide to get an Air Dog.

 

mine was having simialar ploblems. i replaced lift pump no help. some peoeple said injecters and ijesctor pump. mine ran alot better when it was warm out side. when temp dropped back down low, it ran like crap. i couldnt get and power after 1700 rpm. i fianlly took it to a area diesel mech and they run sevearl flow test and found after the motor warmed up it had air in the injector return. they checked the touque specs on the jumper tubes and they said they were loose . tightent hey down and problem solved. there was alot more to this b/s i went through with this truck and this problem but i condeneised it. by the way dodge dealership said it was left pump and injector pump..wanted 4200 to fix...and that was just a est.

 

mj, could you explain where jumper tubes are or possibly post a pic? Thanks.

 

I think he's talking about the injector tubes.They are on the driver side of the head where your fuel lines from the rail go to.To check torque your gonna have to remove all the fuel lines.Factory torque is 37ft lbs on the hold down nuts.There are some good pics on Dynomite Diesel's website in the inj. install pdf.

 

I think that is what it is too. when i went to get my truck..thats what the guy said...he didnt work on it. it was fixed after so long of scewing with it. it was heating up and the heads were expandeing and i guess since they were not tight it was leting it suck in some small anounts of air.

 

I know where the injector tubes are. I think what he is referring to are the "crossover" tubes, which are completely different from the injector tubes. I have heard of them before but I have never been able to get a good explanation of where they are and what they are for. I may need to start a new thread to figure out where they are. By the way, thanks a million mj. Hopefully this problem will be solved simply with the turn of a wrench like yours was.

 

maybe i need to run back by the shop and let them show me what they did.

 

That is extremely nice of you to offer to do that, but I don't expect you to go that far out of your way just for little ol' me. Of course if you just have a burning desire to, go ahead, I can't stop you. But I won't complain at all if you do it.

 

They are the same thing!

 

My apologies. After doing a little research, I think the crossover tubes are the tubes underneath the valve cover. Is this correct?

 

Just follow your high pressure fuel lines from the rail to the head.There is a nut to remove the lines from where they attach at the head.Then there will be a larger nut that is threaded into the head.This is the hold down nut for the inj. tube/crossover tube.It is very difficult to get a socket and torque wrench on the back one.You will have to remove the lifting eye and will need to find a crows foot wrench.Hope this helps.

 

The injector cross over tubes slide into the head you can only see the hold down nut for themwhen they are installed. The pressures are anywhere from 5000-27000psi inside of this side of the fuel system. So any leak at that point will result in a high return flow to the return line. This would happen through out all your ranges of operation not just when you hit 2500rpm.

One problem that some of the 03+ Dodges were having were the fuel lines going from the supply rail to the injector cross over tubes were not torqued properly or were working themselves loose, just enough to allow air to be sucked into them and maybe a tell tale sign of wetness around them but rarly did they spring a visable leak. This was resulting in a loss of power and also excessive fuel consumption.
What work did you have done or mods do you have to your truck?

I still think you either have a fuel or an air flow restriction.

 

that is what was wrong with mine....it ran alot better....alot better when the air temp was above 55. dont ask me why it just did. you would think that once the motor warmed up..wetherit was 20 or 50 it shouldnt have made a differnce but it did. it was a easey fix once knew what the problem was.

 

So I need to remove the fuel line from the crossover tube in order to tighten the crossover tube nut. That makes sense. Will there be any pressure on the fuel lines without the engine running? If so, how do I safely relieve the pressure?

 

No pressure will be on the lines.You will have to completely remove the lines,and the lifting bracket.Don't break the hold down nuts loose,just check that they are torqued properly.Like I mentioned before,#6 is in a tight space and you probably wont be able to get a socket on it.I really don't think this is your problem but its free and fairly simple to check.