2005 yukon xl denali 6.0

[Yukonxljake]

The shop did yes, it loses pressure and then comes up after cranking for 3 seconds or so. I'm on fuel pump number 4

 

[TollKeeper]

Sounds like a bypassing fuel pressure regulator.. But I thought they did away with those in the 2005 model year..

When you say you replaced the fuel pump. Did you replace the entire assembly, or just the fuel pump?

 

[Yukonxljake]

The shop did it, I'm assuming the whole assembly. The 2005 doesn't have a fuel pressure regulator as I've found out. Could a missing cap on the fuel pressure valve up on the rail cause pressure loss ?

 

[TollKeeper]

It shouldnt, and if it did, you would be spraying fuel.

I am finding conflicting statements about the FPR. Some say the 2005 6.0 did have it, and others say it doesnt.

Autozone does list a FPR for the 2005 Denali
Advance does not

I have seen where people have replaced the fuel pump only, and there is a crack in the plumbing inbetween the fuel pump, and the assembly, causing your exact issues.

Would need to find out if they replaced just the fuel pump, or the fuel pump assembly.

 

[TollKeeper]

What it would look like if your did have a FPR

 

[Yukonxljake]

Ok I will look into that! Thank you!

 

[TollKeeper]

What it would look like if you have a fuel pump mounted FPR

 

[Yukonxljake]

I watched that video and he's saying it's on the fuel pump itself, I don't think this year physically had one

 

[TollKeeper]

You would have to look at your engine, and see if that FPR is on the rails.

 

[Yukonxljake]

I did, it is not. That's what I am so confused on how it's losing pressure with no FPR and a new fuel pump.