I havent had the pump in the car for more than 2 weeks with very little run time. This weekend at the IFO in MI i was blaming my ems for cutting fuel out when going into boost. Turns out it was my fuel pump. Put a gauge on a hose and watched it as i took it around the block and its dropping fuel pressure off when it should be increasing. Check voltage and its stays constant.

This weekend i notice it got louder than usual but thought nothing of it. Kept trouble shooting yesterday and the pump quieted a little and started working fine again now its loud again. There are about 8 gallons of gas in the sumped tank and pump sits as low as the sump. Any ideas?

 

the feed maybe to small or you got a bad pump.
is there a filter in front of the pump if what micron?

 

Could your return be too close to your pickup and it sucks air bubbles from it?

 

Authentic Bosch 044 from a reliable source? There is alot of cheap knock off's out there.

 

The feed is a -10an to the pump no pre filter and -6 to the rail. Return is dumping to the corner on the opposite side of the sump. The pump is as authentic as i can tell from a good source.

 

Is the tank vented properly?

No pre filter on a sumped tank is a recipe for disaster. All kinds of crap comes out of old tanks and it's damn near impossible to get all the **** out of the tank when you put a sump on it. There WILL be crap coming out that will end up in the filter... if you have one..

 

After tearing into it more seems like something must have happened with the vent. For some reason it was working fine till we got up to MI must have got stuck or something. I bought the tank brand new and put the sump on it and cleaned the hell out of it then used the POR gas tank sealer. I pulled off the feed hose from the sump and noticed that the fuel flow was not constant, took the filler cap off and it flowed fine. I set the vent up differently and getting a pre filter on it now. Pump seems to work fine but its still kinda loud time for a new pump?

 

Pump being starved of fuel it isn't necessarily a new pump any more. I've had ONE (1) 044 fail. It was on a turbo ZX-14. Starved of fuel multiple times

 

That's correct alpha. The pump uses the fuel for cooling and lubrication of the components. There is a chance that if starved for fuel that some damage has occurred.