I've been having trouble getting power out of my mods. JEGS finally sent my fuel pressure gauge fitting. I checked to see what fuel pressure I've been running, it's was at like 9.5psi. Isn't that stock? I turned that screw as far as it would go and it would never go higher than 10.5 psi. I was turning the screw counter clockwise which makes sense to me(is it right?).

Could my fuel pump be limiting the fuel pressure to 10psi? I just put a new fuel filter on today, no effect on the pressure.

 

my guage reads 11 psi exactly. Maybe your pump is failing....
is it new?

 

I have a similar question, my fuel pressure does not change between 4.3L, 305, and 350 injectors. It is always at 11psi. Don't these throttle bodies have different psi settings?

I am using an Intralux electroninc gauge.

 

This is the same pump I've been using for 2 years ever since I've had the car. My car has always had lackluster performance. I got to work today, the gauge reads 8.5 psi now, it was at 10 psi when I left home. The gauge is new, maybe it's wrong?

 

Where is the gauge mounted? I think a few members a while back found out that heat will affect the pressure the gauge shows (mechanical gauges). The hotter, the lower the pressure.

I have an electric gauge, it reads ~11 all the time.

 

 

According to the literature supplied with Autometer fuel gauges, expect a 1# drop in pressure for every 30° the gauge warms up. If your gauge is T'd and mounted in the engine compartment, it will obviously warm up more than that. Electric gauge would be good. So would tapping into the fuel line outside of the engine compartment. More difficult, but more accurate.

 

[QUOTE]Originally posted by AdmiralNahohkta
[B]I have a similar question, my fuel pressure does not change between 4.3L, 305, and 350 injectors. It is always at 11psi. Don't these throttle bodies have different psi settings?

So, if my electronic gauge dosen't fluctuate more than 1psi between injenctors is this normal? I figured they would have different psi settings. (The 305 throttle body is adjustible and reads 4psi above the "stock" 11psi.)

 

I dunno man.

 

Last night after work it read 11 psi. I've got that tab on the fuel pressure regulator almost all the way up to the top though. Shouldn't I have like a lot more pressure that that?

I'm going to completely block off the hose and see what pressure I get. I read that in another post as a way to check for a bad regulator.

 

2thpick:
The pressure will be the same between injectors. The pressure is a function of the regulator not the injectors. Bigger injectors will get you more fuel at the same pressure. Even if you change the complete throttle body all TBIs work at about the same pressure.

Keith:
Yes, I expect you should have more than 11psi with the reg maxed out. Are you checking and comparing gauge readings with the gauge cold?

 

I am comparing cold and hot. Last night, cold it was 11, hot it was 10, maybe 9.5.

 

Go to max on the regulator adjustment, change the fuel filter if it's not recent. If that doesn't work, disassemble your TBI and check the internal diaphragm. It may have a tear or bad seat.

After that, the pump looks more like the culprit.

 

It's practically at the max, filter brand new, just rebuilt the TBI, new diaphram.

 

I am having the same problem but the other way around, I can't get mine to go back down to 12psi. It just wants to stay at 14. I am running rich as hell. Any thoughts guys?