Fuel odour and LOUD fuel pump

[Marty]

Since I got my car back from DPI 3 weeks ago I've clocked just over 200 miles. A few days ago I started to get a fuel smell inside the car. At the same time I noticed the fuel pump got VERY loud. Outside the car I can't smell the fuel - only inside. I've taken the cover off inside the trunk and I can't find any leaks. When the engine is running and I'm sniffing around the fuel pump, the smell is present but it's much less noticable than it is inside. Today I heard a very strange liquidy squishing/gushing noise from the centre of the car while driving. It made one loud SPLORSH kind of sound which lasted maybe 2-3 seconds. Is it the accumulator?

The car drives fine, accelerates fine, revs fine all the way up to about 6,000 rpm. I have Hervey's pump & baffle.

[Delorean Industries]

If you are smelling fuel from the front of the car I would suggest pulling off the tank boot and seeing if the pump has fuel up inside the boot. How long ago did you replace the pick up set up, and rubber components in the tank? If the clamp around the bottom of the pump is loose or the boot is rotting fuel will come up through the boot.

[Marty]

I can't really smell fuel around the top of the boot. It's VERY subtle. The smell is very strong INside the car. The pump/baffle/pick up hose/entire setup was new about 7 years and 2,000 miles ago.

Can you tell me what to look for, how to pull the fuel pump out, etc? I have 3/4 of a tank of gas. Do I need to drive around and empty it out first?

[Delorean Industries]

Seven years is a VERY long time in the Delorean fuel system world. Drive it around and take the fuel level down to a quarter tank.

Pulling the pump out of the tank will take just a few minutes-

-disconnect the pump harness
-disconnect the large hose clamp around the fuel tank boot
-carefully pull unit skyward

My bet is you will see some fuel down inside the pump boot.

[Marty]

Ok thanks Josh. I'll have to drive it a LOT to get the fuel level down, so it will likely be next weekend. Anyway, if the boot is rotted, why does that make the fuel pump so loud? Will I damage anything driving around in this condition?

[Michael]

When you pull the cap if you see fuel sitting on top of the pump you pretty much have it diagnosed. It does'nt take much fuel to create a strong odor in the cabin, especially in the fuel pump area as the cabin intake vents are right above it.

After you have the boot removed, run the engine and visually inspect the fuel lines to see if there are any leaks there. If not, you most likely have a loose or torn pump boot, and any sudden movement is allowing it to leak out in that area. A tear in the boot might be hard to spot so if you do remove it, check it over carefully.

As far as the noise goes, they may be related, or not. I guess it's possible it's somehow leaking at the fitting and getting starved? Just fix one problem at a time. I was in the same boat with the fuel smell and the occasional pump noise. I chalked the noise up to the common fuel pump howl we get in high temps, and after finding a tear in my boot I thought I had it fixed. Even after replacing the boot the smell was gone but the noise would still occur at times(and cause my car to starve as well) Only after replacing the pump did it solve everything.

[Bitsyncmaster]

When the boot or clamp around the pump is not holding the pump tight, it lets the pump rotate when it starts up. That can twist the pickup hose and the supply and return hoses. Over time that can lead to a loud pump and leaking fuel.

Hervey's power pump which had a foam cover around it because it's diameter is smaller, caused that problem with my car. The foam rotted, broke the pickup hose and tipped sideways. Maybe he uses a better foam now.

[Marty]

Sounds like my pump could be tipped or twisted then. Once I get the fuel used up I'll get to it. We have a club meet on Saturday, so maybe I can do it then.

As far as the noise goes, they may be related, or not. I guess it's possible it's somehow leaking at the fitting and getting starved? Just fix one problem at a time. I was in the same boat with the fuel smell and the occasional pump noise. I chalked the noise up to the common fuel pump howl we get in high temps, and after finding a tear in my boot I thought I had it fixed. Even after replacing the boot the smell was gone but the noise would still occur at times(and cause my car to starve as well) Only after replacing the pump did it solve everything.

Ok, thanks for the tips! The noise definitely coincides with the smell. When I first start up the car (after it sits overnight) the pump is quiet and there's no smell. But after about 20 minutes of driving, the pump gets loud and the smell intrudes the cabin at exactly the same time.

[Ron]

Please think twice about driving around with a fuel leak...

[Marty]

I don't have a fuel leak. I have looked everywhere. It's all dry.