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Engine/Transmission (1998.5 - 2002) Fuel pressure starting

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I have a 2002 2500 with dealer conversion in tank pump and I just installed a direct pressure fuel gauge
What I noticed right away is I'm not getting the first stage fuel pressure when I turn the key on.... it does pressurize after I bump the starter
Is this going to be a problem of starving my pump of fuel later as my pump I'm assuming will start to lose pressure I currently have 14 psi at the vp44 pump that's the port I tapped for my pressure gauge
Is this a fix I can repair or is it a ecm problem ???
Pappy
PS: I have swapped the relay this wasn't the problem
 
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If you're getting 14 lbs with the in-tank pump then chalk that up as favorable.....and rare. The block mounted Carter lift pumps barely put that much pressure out, and the in-tank pumps typically didnt reach over 10 psi.
Yes I'm an advocate for tossing the OEM fuel pumps and achieving no less that 14 psi under all running conditions with an aftermarket fuel pump, but unless you're regularly seeing the running pressures drop below 10 psi with your current pump, I'm not sure I'd tell you to run out and change anything. Well that is as long as the fuel pressure gauge you're using is accurate and telling the true pressure.....

Why you're not seeing the initial 2 second prime cycle, I cant say. But nonetheless, its not required unless the fuel system has a small leak and is allowing the prime to be lost. So as long as it starts normal, dont sweat it. :)
 
I'm OK with my current pump pressure it's the 2 second pressure that I don't have and was wondering about.... apparently it's a ecm problem of not turning on the pump and i would like to have everything working like it should work
So is a dealership the only place that can fix this ???
 
I wouldnt do anything unless you think its not starting normal or there's any fuel pressure related problems. The odds of a dealer fixing anything is slim, but you can be sure they'll take a lot of your money. :)
 
I'm having a problem starting that I didn't mention when my truck sits for more then a couple days it's hard to start I need to engage the pump 2-3 times before it will fire and run its not something terrible but it's annoying sometimes
Pappy
 
Pappy, that usually means an air leak somewhere. I'm fighting the same situation on my 2001. I found the threads on my water valve were shot, and not holding the valve body tight to the o-rings. You can see
my fix on my canister thread. I just finished it today, so still don't know if that's what was causing my hard starting after it sits for awhile.
Jim
 
I'm having a problem starting that I didn't mention when my truck sits for more then a couple days it's hard to start I need to engage the pump 2-3 times before it will fire and run its not something terrible but it's annoying sometimes
Pappy

If it extra cranks in the morning or when its been sitting for periods of time then yes, thats generally due to a leak somewhere in the fuel system. The most common places to leak are ANY fitting you've messed with lately, or the single banjo bolt on the back side of the head (injector return), or the tee fitting just below that banjo, or the water drain valve on fuel filter housing.

The way you can tell if a leak is the real problem is by parking the truck with the nose pointing downhill. This raises the rear which prevents gravity from pulling the fuel out of the fuel lines and into the tank. If you park it like this and it starts more normal in the morning then a leak is the issue. :)
 
There is some truth to that, but it isn't that simple. You have to park at enough of an angle to get the fuel inlet of the filter canister above the injector pump. As long as the canister inlet is below the injector
pump, gravity can drain the fuel into the tank if there's an air leak.
Jim
 
That wasn't a fix I parked nose down on a steep hill let truck sit a couple days
Tried to start same thing bump starter 3-4 times to build fuel pressure " it does pressurize to 14 psi" try to start no start until 4th time then it starts
I've got a sigh tube that I used on big trucks to check for air in fuel system I'm goin to try that next
Pappy
 
I did that with mine yesterday, and it started fine today, Pappy. I'm still chasing my air leak, so I sympathize with you. You might take a look at Blue Chip Diesels troubleshooting page for ideas.
https://www.bluechipdiesel.com/troubleshooting.html

Pay particular attention, after your recent test, to what they say about trying to start it with the lift pump disconnected from its power source. That test is to determine if you have a hole in the injection pump's
internal diaphragm.
Jim
 
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My 01 did this once changed every o ring on on the delivery side to the injection pump and even the fuel line from tank to filter it ended up being a o ring on the cross over tube on an injector
 
Blue Chip mentions that in their troubleshooting guide. In the case of my truck, I'm hoping that isn't the problem. I installed new o-rings on the tubes in October last year, so I assume they're OK. My problem
came on all-of-a-sudden, too. One day fine, the next, hard starting. I found one small thing yesterday.....will get back with that if it solves the problem.
Jim
 
Yes, aside from the common place leaks I previously mentioned, there is the possibility of injector pintle valves leaking down or crossover tube o-rings leaking, or bad injector/crossover tube alignment if injector install was recent.

But other than that, dont worry about the VP diaphragm as this is an old false internet tale which can still linger on today. Thats not to say the VP itself cant cause a hard start issue but typically it would be related to a hot engine hard start. :)
 
What am I missing? The last 3 posts mention cross over tube O-rings leaking. If a crossover tube is the same as the Injector Connector Tube, that seal is for oil only, not fuel.

Nick
 
The crossover tube is the connection between the injection pump line and the injector. If the o-ring seal on the crossover tube, or the mating surfaces or the injector/crossover tube, are leaking then the prime within the fuel system will be lost as the engine is off. Then the fuel lines will have to re-prime in order to start the engine.
 
Are you talking about #2 in the bottom scan?
001.jpg

I don't see any other o-ring on the connector?

Nick

001.jpg
 
I think I found my hard starting problem my #4 injector line was dry when I cracked it open so I'll replace that injector line and I'm hopefull it's the problem
Pappy
 
I don't know why I'm just going on my 50 years as a diesel mechanic I was taught to check each one and #4 was the only dry line so I'm goin with it
Pappy
 
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