Vortec 454 Revs up high then dies HELP!!

[Christian Steffen]

25, the long term trims were at 50

So it's lean, they're adding fuel. Check your fuel pressure.

 

[Brice Edwards]

So it's lean, they're adding fuel. Check your fuel pressure.

What's a good fuel pressure for it to be?

 

[Tom P]

Anywhere from 48-56 would be acceptable. 56 is spec. My truck runs at 48ish but has run as low as 30 and will continue to idle once the fuel pump relay is pulled and fuel pressure has dropped below 10.

 

[Christian Steffen]

Technically, key on engine off should prime to 58-62 pai.

 

[Tom P]

Technically, key on engine off should prime to 58-62 pai.

Well then I really should swap my fuel pump.

 

[Brice Edwards]

I got 52 at prime and 49 at idle

 

[Christian Steffen]

That's not helping. Probably need to resolve that before going any farther. You said you replace the FPR right?

 

[Tom P]

I got 52 at prime and 49 at idle

Those numbers are higher than my truck and it runs "ok". Two weeks of sub freezing temps at night means it cranks a little longer to start in the morning.

 

[Tom P]

Have you tried disconnecting the battery to reset the fuel trims?

 

[Brice Edwards]

yep, 3 times