Fuel Pressure PSI...

[usamarshal]

Quick question for anyone that has a 5.7 Vortec Tahoe...years 96-99...do you know what the fuel pressure is supposed to be? I'm running 60 PSI right now and didn't know if that was the standard or if its to little or to much...thanks, Andrew

[Blue Bowtie]

61 PSIG minimum rail pressure for proper starting.

As somone of prominence would say,"Don't leave home without it."

I've seen them start and run as low as 58 PSIG, but barely, not reliably, and not without problems. Whenever I install a new FPR, I try to set if for 63-65 PSIG under no vacuum, then verify the drop with 15" Hg applied.

[Mr. Smith]

Originally Posted by Blue Bowtie

61 PSIG minimum rail pressure for proper starting.

As somone of prominence would say,"Don't leave home without it."

I've seen them start and run as low as 58 PSIG, but barely, not reliably, and not without problems. Whenever I install a new FPR, I try to set if for 63-65 PSIG under no vacuum, then verify the drop with 15" Hg applied.

I have 58 to the rail...Starts everytime no issues

[MT-2500]

Originally Posted by usamarshal

Quick question for anyone that has a 5.7 Vortec Tahoe...years 96-99...do you know what the fuel pressure is supposed to be? I'm running 60 PSI right now and didn't know if that was the standard or if its to little or to much...thanks, Andrew

There is several fuel pressure readings you should check.
Engine crank and engine running and running on the road and leak down test.
And remember some gauges may be a little off.
Here is the guide lines for fuel pressure test.
Good Luck MT
Hard to start cold.
Check cold start fuel pressure.
Check engine running fuel pressure.
Check engine running on the road fuel pressure.
Then shut it off and watch for fast leak down.
Pinch off at rubber part or block off return line and check full pressure.
Later V6 and V8 gm engines should have 60-66 fuel pressure.
Cold start should be 64-65 lbs of pressure.
If you do not have full fuel pressure on a cold start the injectors will not squirt fuel.
Do not leave home without it.
Engine running should be 60-66 lbs pressure depending on engine load.
Full pressure with return pinched off should be 75-85 or more.
And if it has a fast leak down after shut off you have a leak.
Post back fuel pressure readings.