mshobe

There are a few drops of fuel steadily dribbling from a seam between the underbody and the lower driver's side door trim, right about even with the door handle. Car parked on level ground. I just noticed this for the first time tonight on my '89 C4. I topped off the fuel tank about 15 miles ago, so that may be a fact of note. No fuel smell or dampness anywhere near the tank, or anywhere else on the car that I can tell, anyway.

Streather's book shows a fuel vent air flush line from the charcoal canister mounted near this general leak location. That's the only fuel system component anywhere near where the leak is, so unless the leak is being funneled to this location from the centrally located main fuel line, I'm at a loss to explain it.

Anyone seen something like this before?

Rocket Rob

I would suspect you have a defective gas cap seal. My cab would have a gas smell right after filling the tank. It would make the most smell when I made a right turn. I discovered that the fuel was coming out at the gas cap and then draining out the water drain tube in the gas filler. I purchased a new gas cap, no more smell.

jimq

the fuel pump isnt far from that area under the car. Check to see if its wet around the bolted on entry panel for the pump.

newsboy

If it's coming from the gas cap seal, you should be able to determine this by putting a small rag in there to see it it stops, or gets wet. Could also be fuel pump related (as mentioned above). If the banjo fitting on the pump loosened up, gas could run down the front pan. You really want to determine where the leak is coming from, before you drive the car.

mshobe

Thanks all. I'll check the cap for leaks (hell, maybe I didn't seat it properly) and investigate around the fuel pump location. Very very little fuel seems to have leaked since I posted so I don't suspect it's something draining low enough in the system to be drawing from the tank itself. (At least I hope not.)

LouZ

Many times it ends up being the gas filler neck. That piece would warp over the years due to the gas pump fill nozzle resting on the bottom of the neck and elongating the opening, thus preventing a proper seal with the gas cap.

Porsche has revised the part a couple of times to address this issue. A new neck is about $100, and 20 minutes of work.