Hey guys,
Installed my walbro gss340 yesterday. The truck and fuelpressure are great when the engine is running, BUT......

When i get in, and put the key in and turn the ignition to the "on" position (not start) the fuel pressure goes to 54 like normal, but then starts to drop in incriments of 10 all the way to zero pretty fast. If you try to start it, it sputters and stops. You have to take the key out and put it back in, and start the truck before the fuel pressure drops. On the first start of the day, there won't be any pressure in the lines, it sputters like it were to if i had waited to start it as described above. I hooked all my lines back up... what is happening to my fuel pressure? It's supposed to be the same whether the engine is running or not???

Please help
Nate

 

sounds like a leak or faulty pump.

 

Faulty pump? christ if i would have to go through changeing it out again and buy another one that would BLOW. The pump is fine when the engine is running though?. I looked under the truck there doesn't seem to be any leaks comming from any of the lines or connections???


Nate

 

did you ever disconnect the fuel lines to the manifold?

 

Bit confused, manifold? you mean the three lines that connect to the modual that sticks out of the tank?

Nate

 

No, the intake manifold.

 

Oh no never touched that stuff. Only disconnected the fuel lines on the tank. Is there a check valve on the tank that might be faulty now or somthing?

Nate

 

If the tank is the only place you touched the fuel system. Then, more than likely that is where your problem is. Sorry.

If there's no fuel leaks anywhere, then that also points to an in-tank fuel pump issue.

Fuel leaks shouldn't be too tough to track down with the associated smell, although gas can evaporate quickly.
check the schrader valve on the intake manifold to make sure its not leaking,
Sounds like you need to drop the tank again.

 

Ok so i'll drop the tank.... what should i look for? do i need to just order another pump and replace it? Is it pump faulty if it runs fine when the engine is running? Does in intank pump feed line hold pressure in it? or is there a check valve after this line?

Nate

 

TTT
Nate