Ive got a quadzilla cammander with one of the new 0-40 psi sensors. As i was driving yesterday 400mile trip i noticed that my fuel preasure was all over the place with no rym or reason. I of course pulled over and checked both pumps both are working. Ive got a lp on the block and another one relocated back by the tank. I know this because i could hear both of them while running, by using a a braker bar and an extension i could hear the wourring noise over the engine and then i also hit the starter to start the 30 sec pump sycle both times i could hear both pumps. I then checked all the wiring thinking mabe a fray or something or losse wire but everything looks good.

So do i have a lift pump that is intermidiatly working or is my sensor gone **** up? I am sure quadzilla will take care of me if thats the problem but i want to get some opinions before monday when ill be giving them a call.

If you can think of something else that i might be over looking im all ears.

Thank You

 

I've experienced the exact same thing but using a mechanical gauge. Long and short the LP was bad or maybe a fuel line. 16psi idle down to 9 for no reason. Replaced it with a Walbro yesterday and no more funny pressure readings. I traced all the fuel lines and put on hose clamps on the hard line to fuel line connectors thinking air was getting into the system, no fix. While removing my old fuel lines yesterday the connector at the engine mount lp seemed really loose and the blue tabs the hold the line on were pretty worn, the line would not pull off until the tabs were depressed but if it jiggled the fuel line I could hear a difference in sound and see a difference in pressure, from 9 back to 16psi. I'd start there but plan on a new lp in the not so near future.

Good luck.