Fuel Pressure Specs for 5.7 L Vortec

[El Daddio]

Hi all. I've read through most of the posts here. What is the correct spec for fuel pressure on a 5.7 L Vortec in a 2000 GMC Yukon Denali?

I tested mine, got 51 psi key on engine off, and a brief dip then consistent 50 psi with engine running at idle. I turned it off, and pressure holds, not bleed down.

I've read 60 - 66 psi is needed. Is that correct?

 

[exp500]

5.7 vortec cast iron- usually listed as 98 and older- 62-66 correct. The LS runs with less.
Are you experiencing problems? Describe please.

 

[El Daddio]

Starts fine, occasionally stumbles a bit around town (seems like random misfire) but runs out of steam at speeds over 70 mph - it suffers random misses, etc. at that speed.

I am also checking cylinder pressure, ignition, but haven't gotten there yet.

 

[exp500]

Do you have a code reader? Any codes? Bafx is a decent cheap one, but if computers don't frustrate you too bad, this is best.
Vxdiag VCX Nano for GM/Opel Diagnostic/ECU Programming Tool

 

[exp500]

You will notice misfire codes, O2 codes and maybe fuel trim codes. Recommend a live data scan including fuel trims at various rpms, short and long term.

 

[El Daddio]

Will the tool you recommend measure can retard?

 

[exp500]

Both will.

 

[El Daddio]

Thanks. I meant cam retard of course!