Is it my fuel pump or my imagination?

[Matahoe]

Quick question - In A 2004 Yukon 5.3 flex what brand is the factory fuel pump? ACDelco or Delphi? Thanks.

Acdelco doesn't make fuel pumps they just rebrand them for the aftermarket. It's probably a Bosch which is what came from the factory in my 2005.

 

[Justinj360]

Acdelco doesn't make fuel pumps they just rebrand them for the aftermarket. It's probably a Bosch which is what came from the factory in my 2005.

I forgot about Bosch. Well between those 3 brands who would you say makes the best fuel pump for these?

 

[Matahoe]

ACDelco Original Equipment, Airtex or Bosch is going to be best in the long run imho. I would skip store, ACDelco Professional or ACDelco Advantage brands. They tend to be cbeaper made in China. I just bought a Bosch fuel pump on Amazon a year ago. It was around $110 open box. The hardest part replacing it was removing rust from everything, fixing the nylon lines and removing the locking ring. Make sure you get a new one.

 

[Maximus1]

The other day while driving with the wife, she was yelling at me because the low fuel light was on. NP I told her, there are 6 gallons in reserve. 30 seconds later....rolled to a stop. Got some gas, started right up, in fact right up, didn't even cycle the fuel pump. Drove home, 2 minutes away. Went to go to take it to the gas station and would not start again. Put some more gas in, started. Drove 2 minutes away, and counting the gas I put it, it only took 26 gallons. In other words I was not out of gas. So I got out the old fuel pressure gauge. This is where it gets confusing.

When I cycle the engine, I get 58 psi, but after 3 seconds, it drops to 49 psi. After 5 minutes it drops maybe a lb. So, is this normal and I have a problem somewhere else?

2005 GMC Yukon Denali XL 6.0 AWD

Yes it’s normal. The fuel pressure regulator is adjusting the pressure based on the vacuum pressure of the intake. The lower the intake vacuum pressure the higher the fuel pressure.

 

[JonnyTahoe]

Quick question - In A 2004 Yukon 5.3 flex what brand is the factory fuel pump? ACDelco or Delphi? Thanks.

Hmmm What ever was available at the time they were built.

 

[JonnyTahoe]

ACDelco Original Equipment, Airtex or Bosch is going to be best in the long run imho. I would skip store, ACDelco Professional or ACDelco Advantage brands. They tend to be cbeaper made in China. I just bought a Bosch fuel pump on Amazon a year ago. It was around $110 open box. The hardest part replacing it was removing rust from everything, fixing the nylon lines and removing the locking ring. Make sure you get a new one.

Great advise.