BlackCloud#2

When I go to start my pickup it starts really hard like the truck is loosing fuel pressure or there is a hole in the line and I can't find any leaks or holes anywhere. It isn't throwing any codes that would say it is the fuel system. Any one had this problem, it just started a week ago, and does it somewhat sparadically.

scottsjeeprolet

What kind of fuel pressure do you have?

xtoyz17

Is it after sitting for awhile, or does it not matter?

BlackCloud#2

The fuel pressure is good 18 psi when idling and 15 down the road, but now i am finding that the fuel tank is becoming pressurized.

scottsjeeprolet

Last time we had that happen it was the injector hold down bolts. They didn't get tightened down. Check your hold down bolts, if they are ok then it could be an injector oring.

xtoyz17

Never answered? If it's after sitting for awhile it's some sort of air leak. If it's sporadic and independent of time sitting it might be an injection pump.

scottsjeeprolet

An IP problem wouldn't pressurize the fuel tank. Gotta be an injector related issue. Cross over tubes, oring,washer, hold down bolts. Things you need to check.

xtoyz17

Isn't the tank always pressurized to some degree? After all, the tank is sealed and you have return pressure?

On the other hand, isn't there a breather on the sending unit that should NOT have the cap on it, so that the lift pump can never pull vacuum? Should the opposite be true (not being able to pressurize tank)?

Just asking questions here, I honestly don't know and am curious...

Shawn

scottsjeeprolet

The tank is vented otherwise it would explode or implode with the temp changes or as the tank drew empty it would collapse the tank.

Busboy

I notice you have a FP gauge, did you use an isolator? If so the grub screw (Allen head) for bleeding is supposed to have a ball bearing under the screw. If you took it out the ball could have fallen out. The grub screw will seal enough to prevent a leak but allow air in over night.