HELP NEEDED: Leaking fuel

[thdrill]

Over the last few days I have been noticing a dramatic decrease in MPG (like only 60 miles on half a tank of gas) and an associated gasoline smell after parking my Tahoe, even on short trips. Today when I got home from work I looked under the truck to see if there were any leaks and noticed gas dripping from the top of the tank that stopped after turning the truck off. I am thinking that it is fuel pump related but cannot get a good look as it is night here. Are there any suggestion for where to look or how complicated it is to drop/reinstall the tank.

Any assistance you could provide would be greatly appreciated.

 

[Vette66]

Not sure but I am sure somebody has done this before.

 

[WHITEOUT]

I just replaced my fuel pump last year. Not exactly hard, but I hate dropping tanks. There are some good videos on YouTube about fuel pump replacement. But its really only 2 bolts & straps you have to remove, that hold tank up. Then the filler hose, vent hose and fuel lines ect.. biggest pain is when tank is full, shit is heavy, and how it's wedged up there.

I would think if it just started, could be a line, filler hose or vent hose leaking. Maybe try and turn key to on position to get fuel pump activated, get under the vehicle and check around, looking for where it is leaking. May be something you can fix or replace without having to drop tank. Or at least give yourself an idea what it is before dropping tank and going in blindfolded, so to speak. Will be hard to tell without it actually leaking since gas evaporates pretty quickly.

 

[electro]

^ Ya.

But just running your tank to 1/8 tank or less and then let it down..

You need to raise rear of truck and squeeze in there.

First loose and free the drain and vent hose from the back left corner of the tank. Few hose clamps. Spray a little penetrating fluid on them and they will move well.

Loosen the two bolts that hold in the straps up. One bolt per strap, 17 or 18mm maybe. If you can get something to hold the tank up it helps. I did it by myself and just used my knees and arms and let it down easy. If you had a partner for 5 minutes when your ready to let it down and 5 minutes to put it back up, it would be a breeeeze.

Anyway, get it down out of there and inspect the top.

Maybe have helper turn key to pressurize fuel system while you watch for leak.