2003 vortec 6.0 - fuel pressure problems

[westman995]

How likely is that, with a brand new ac delco pump?

I swapped two injectors around and the misfire seemed to follow it so looks like it need's some injectors.. when I changed the pump the tank had dirt n shit in it so I cleaned it all out n put a new filter on it.

Injectors looked dirty when I took them out

 

[SLCHOE]

Pull your upstream O2's out. Go for a drive.

 

[westman995]

What would that do?

 

[01ssreda4]

My original post was before I replaced the cheap pump with the ac delco pump. The pressure is now higher at around 48 while running if I recall.

Weird thing is if I turn the key on it jumps up to 58 or so then drops right down like 10 psi and then it'll slowly bleed off from there.

I ended up ordering a regulator so I'll see what happens after that

This is not within spec per the service manual. I know this as fact because my truck had the same issue.

 

[westman995]

Well what else can cause the low pressure? I put a brand new ac delco pump in it and itsee better than it was but still not very high.

I need to get a new hose for my fuel pressure tester cuz the pin thing fell out of the end of it