Well, I guess I should have expected it. Finally got my FP gauge hooked up and found that my readings were, well, shall we say LESS than stellar??
After proper bleeding and rebleeding and such, I have about 5 or 7 pounds (according to the gauge) at idle!! When my mechanic hooked up his FP test gauge to the schrader valve directly, he said he read about 5.5 or 6 pounds. While driving, at even 1/2 throttle, my gauge dropped to zero. Now, I KNOW that I cant be pulling zero pounds of fuel pressure or the darned thing wouldn't run.... Would it?
I did see 8 or 9 pounds at idle and just under 5 at about 1/2 throttle for a bit on the way home, but it didn't stay like that for very long.
So great. Sounds like I'm going to need a lift pump. Oh joy.

 

YUP it sure will.
The Injection pump has a small fuel pump that supplies itself with enough fuel to run.
The Lift Pump supplies that, plus additional fuel that is used to cool the injection pump, then returned back to the fuel tank.

Check your PMs for a location to get a pump for substantially less than the $350 that Dodge dealers are charging.

 

So that begs the question. Is the lift pump a warrantied item in DCs 5/100 engine and powertrain coverage?

 

YES it is covered if you decide to go that way.
I think it's actually covered on the 100,000 miles Cummins fuel system warranty.
Some dealers will dispute this and some will tell you that even if it's only showing 3 or 4 pounds of pressure it's "OK".

I prefered to purchase and install my own lift pump both times (I'm only at 79,000 miles now) rather than let them mess with my truck.

 

Well, they are already putting a turbo on on Thursday. I'll ask about the low pressure. I believe according to AllData, the idle pressure should be 10 pounds.
Someone can correct me if I'm wrong here.

 

Idle pressure won't tell you anything about the performance of the LP. There is no point in having an idle FP "spec". You need to know WOT FP to be able to verify the performance of the LP......5 psi is the minimum acceptable WOT FP but as we all know, we want to see more than the minimum - makes us feel better!

 

Thanks.
And at WOT, I am decidedly UNDER 5 pounds.

 

I see 16 psi @ idle.
I can pull it down to 10 psi @ WOT with only a Comp box.
If you're starting at 10 psi @ idle, even totally stock you're surely going to see less than the 8 psi @ WOT that most agree is the minimum.

 

Well, given that my fuel filter was replaced at my last oil change last week, I don't think that my filter is clogged.
It's interesting as I am driving, I watch the needle hover at 5 and drop to zero. But then I'll look back and at idle I'm up at 8 or so and when I get on the throttle it drops but not to zero. But then, as quickly as it goes up, it goes right back down.

 

Yup, the LP is pooched!!!......that is why you see erratic FP readings.....replace it ASAP!!

 

Thanks! Truck is due in on Thursday for turbo. I will mention it then.

 

mine was running with a lp that had no fuel pressure...I opened the system and I guess it lost its prime and then it would not restart. Replaced the lp and the truck runs great now

 

What kind of FP guages are you guys using. Looks like those things are $$$$$. Is there a good inexpensive one to get????

 

They're pretty cheap when compared to a $1,000 Injection Pump.

 

It only $34.99 at DPP...

http://www.dieselperformanceparts.co...unique=C305424

I bought my full set plus the pod for $309 and worth every penny!