AlbertBlue

I have a 1971 911E Targa, with the original MFI. The car makes my garage smell strongly of fuel, and I and my clothes smell of fuel after driving it. My mechanic has inspected the fuel lines and replaced some. The vapor box in the fender has been repaired for leaks. The smell is strong right around the fuel filter and left side intake after the car sits. From other posts I suspect fuel is sitting in the intake having to do with the cold start mechanism, but he has checked that out. We have spent a lot of time trying to run this down. My wife is not happy with the smell of the garage. This is not run of the mill old car smell. The car runs great though from the black on the tailpipe probably on the rich side. The mechanic tried to lean it out but that affected startup. Any help would be greatly appreciated!

dunlopnick

have you checked fuel filter and associated lines in engine bay ? Is there any fuel dripping onto the ground ? Have you checked fuel pump and assoiciated lines ...

you could also post on early S registry - wealth of know-how there

AlbertBlue

Thanks for the response. Mechanics have checked all the fuel lines. There is no apparent leak at the fuel filter but I think we should replace it, the smell is right in that area. It drips about one drip of oil per day, no gas that any of us can tell. Fuel pump seems ok and there is no smell in the frunk.

I've read that the MFI should be rebuilt every 50k miles or so. It has about 86k and has not been rebuilt to my knowledge. Could that have anything to do with what people say about fuel pooling in the intake? Might having it rebuilt solve it? Expensive but worth it if that is the problem.

I'm running an experiment I'm going to check tomorrow. I temporarily closed up the intake with plastic, I want to see if that makes a difference while it sits.

myflat6

I am not an MFI expert, but removed my system and have been getting components rebuilt. I will learn more as I install everything back on my motor. However, I believe the outlet from the fuel filter console (to pump) is a check valve. If this is true, maybe it is leaking slowly. But then again, I am not sure what this would mean to the MFI pump -- would it overflow into the intake? You checked both your electric fuel pump and the big MFI pump for leaks?

Spyerx

I don't know if this is your issue but on an 89 EFI car I was getting fuel smell, very strong, and it wasn't leaking, but some of the vent lines were permeating odor as they were pretty extensively cracked on the inside... totally different system obviously. My 71 only is gassy smelling until the fuel in the carb bowls evaporates :-)

If you don't know the age of the soft lines on the vent and fuel system it might be worth a change over...

AlbertBlue

Thanks.

AlbertBlue

Thanks. I'll ask the mechanic to check those out.

Jim
1971 911E Targa

AlbertBlue

Ran a dye test and definitely fuel in the intake. Taking off the cover there is a strong fuel smell from both sides. Mechanic suspected the cold startup which dumps raw fuel into the intake. We disconnected that but still same smell. Car has 86k miles and I don't believe the MFI has been rebuilt. Can they leak internally? The check valve from the cold startup at the fuel filter is working.