Any body here have an Autometer Fuel Pressure Guage on their LT1? After first installing it, it read a constant 60 Psi. Now after finally taking a look at the wiring, turns out that one wire had popped out while I was putting the kicker panel back on.
So now that it;s all wired together, I'm getting what I think are wierd readings. At idle, it sits @ 60psi, WOT @ 70PSi and when I let off the gas it drops straight to about 15psi?Then when I touch the gas it goes straight to 70 again?? Is this normal????

 

No... not normal. Do you have an adjustable fuel pressure regualtor?

When you turn the key on, but don't start the engine, fuel pressure should sit at 43.5psi +/-2.5psi, so anything in the range of 41-46psi is OK. When you start the engine, the vacuum will pull the fuel pressure down 5 to 8 psi, so at idle you might see 35-38psi. When you go WOT, you lose vacuum, so the fuel pressure should go to the same level it was at with the key on and the engine not running. So, you should see the fuel fluctuate over a pressure range of maybe 35 - 46psi, depending on throttle postition.

Sounds like you have the wires crossed.

 

thanks, I'm gonna go see what I can do.

 

ok, the wires fine, and no I don't have an adjustble fuel pressure regulatar. Any other ideas, could the guage actually be faulty?

I bought the guage with the sender unit that goes to the black box and then to the guage. I can't figure it out.

 

I just finished installing mine 2 days ago. At idle mine reads ~38psi and under load ~45psi. So if you don't have an adj FP regulator I think possiblly a bad sender.

 

Is you gage an autometer cobalt? Mine is and it is acting wierd also. Sometimes it reads what i think is the correct fuel pressure then after shutting the car off and restarting it may be on 60 at idle. Repeat and it could be on 80 next and then will not go down till after the car is sitting for a long time?

??????

Maybe there is something wrong with this gage!

 

I'm not sure what is up with the hi pressure, but the fact that it stays after the car is shut off is normal. The pressure will decay after a period of time.