Mysterious Fuel Pump Question

Hello Everybody, I have an '83 Rabbit GTI. It was having trouble starting sometimes when it was hot. It was getting spark, so I determined it might be a fuel supply problem. I removed the fuel filter, and the stuff that came out of it was a muddy brown liquid - very dirty gas. With the fuel filter removed, I turned the ignition, and looked at the fuel supply hose fitting where it attached to the filter. Nothing was coming out. I thought that the filthy filter may have helped destroy my fuel pump (overworked it), so I replaced it with one that worked when I took it off my other Rabbit. When I hooked up the electrical leads and turned the ignition, the motor clearly was spinning powerfully. But when I hooked up the fuel lines and cranked it up, nothing came out of the fuel supply line where it attaches to the filter. Is it possible that the fuel supply line from the pump to the filter is blocked with filth? OR, am I wrong in assuming that fuel should come out of the fuel line when I crank up the ignition? Any ideas? I would very much appreciate anyone's input. Thanks, Fred

The part near the bottom of the gas tank that collects the fuel. It generally has some sort of screen on it often call a sock. That screen can get clogged.

If it is clogged, then it is likely you either got a bad load of gas, or your tank is rusting.

In all those cases a good shop can clean the tank (I believe an acid rinse is the usual method) and then, if needed use a protecting material in the tank. Motorcycle shops do this a lot. I would not recommend this for a DIY project. If have the book with instructions and can handle the existing gasoline, you could do the removal and re-install yourself, but I find that is usually a nasty job.

Take it to a rdiator shop for cleanup. Or go find Eastwood on the internet for resotration kits. If you happened to live in the south going to a junkyard and getting a "new" tank from a car that has a gas cap on would be best. Plan on replacing all injection components if your tank is that messed up. Yes everything. CPR, injectors, fuel distributor. CPR and distributors can be salvaged from a 85 or 86 Jetta. At least that is what I got when my CPR and distributor acted up from a gas tank that had no cap and an engine bay with no hood. Junkyard salvage project that served me well for 150,000 miles once I fixed it up. Still running.

Muddy brown is not gas. That is water. Disaster to fuel >Also, how does one clean a gas tank?

Jim B.

Also, your car may a second fuel pump called a "transfer pump" which could be bad, or its input screen could be covered with crud. I don't know what years had this pump, but my '86 Cabriolet has one, and my car has basically the same 1.8 engine as 83-84 GTi's.

I beleive the second pump came into existance for the A2 chassis' but don't quote me.

On A2's and later perhaps, there is the fuel pickup pump mounted in the top of the gas tank, it is gotten to from an access panel inside the car near the spare in a Golf body style, and I *believe* it is under the rear seat in a Jetta. Its got feed line, return line, and electrical connection.

The main fuel pump is located under teh passenger side of the car in a mounting whihc includes the fuel filter.

Sure is.

Yes it is possible, but I would not suggest common for the fuel to flow "freely" with the sock clogged. I might suggest that if there is a rubber hose involved between the pump and the tank, it could need replacement. It might be collapsing (even if you don't notice it on the outside) when the pump starts and that can also restrict fuel flow.

Is this part inside the gas tank?

It is just a screen to filter out the big gunk at the inlet of the fuel line as it goes into the tank.

It is on "carry over" A1's like my '86 Cabrio, but may not have been on A1 hatches or Jettas.

You get to it from under the rear seat in an '86 A1 Cabrio.

Jim B.

I removed the "out" line from the accumulator, and cranked the engine. Fuel came shooting out with great force, so I'm assuming there's a clog in the line between the accumulator and the filter under the hood. I'm going to try the carb cleaner option to see if I can clear that line, unless someone knows of another link in the chain that may be the problem. Chilton's doesn't show anything else between these two parts. Any advice or comments on the carb-cleaner procedure? Thanks again for your help, everyone!!!

For those who may be researching the same problem, it turns out that the problem was the fuel pump relay. Before they completely die, they can be hit-or-miss for a while. That caused my fuel flow/clogging misdiagnosis.

thanks for the update! glad you solved the problem too!