20chevy01

to start what should the 5.3 fuel pressure be?? i changed the fuel pump this past weekend, and has a new fuel filter. with that it will start and idle fine, when i go to accelerate it bogs down all the way, my pressure reads 40 at an idle and drops 5 to 10 under a steady acceleration.. i am strongly leaning to the fuel pressure regulator is bad, any thought???

Atomic

iTrader: (42)

im guessing its a return-style, in that case it should be 50 at idle and 58 at full throttle. Sounds more like your pump is going out. How many miles on it? The stock fuel pumps usually go around 100k

1SlowHoe

iTrader: (28)

He said he replaced the pump...I assume with a new pump?

Was it doing this before and thats what promted the pump replacement?

charcoal03silvy

iTrader: (1)

me and my dad both have almost 120K on our trucks and haven't replaced a single OEM thing

Atomic

iTrader: (42)

Oops, I read filter instead of pump. Yea change the filter and reg, both are pretty cheap and easy.

I said usually go around 100k

20chevy01

i replaced the pump with a new fuel pump this weekend. the filter was changed about 5 weeks ago cuz thats what i was thinking it was. and yea it was acting up before the pump and filter.. now both are brand new and its still acting up. im stumped and i am almost completely sure its got to be the reg. but the pressure is staying right around 40 psi and drops at full throtle.

but if i gradually build up to i can get the rpms up all the way, but very slowly

Atomic

iTrader: (42)

I wouldnt recommend doing that. Chances are you are running very lean in the process, go ahead and ask me how fun it is going lean at full throttle

1SlowHoe

iTrader: (28)

Unless you have a "Z" in your vin (Flex Fuel) then your 40psi is low. I'd replace the FPR and see. Easy and cheap...

1SlowHoe

iTrader: (28)

Looks like this ...

Atomic

iTrader: (42)

I was going to say this