Quote:
Originally posted by mike mueller
nope, that's the way the L-Jet supposed to work 
with the key on, and the movement of air past the flapper, the dual relay energizes.....one relay turns on the fuel pump, the other relay gives 12v to the injectors.....
sounds like you have a major vaccum leak
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Mike, you are close, but no cigar.. ;-)
there is a Yellow wire in the engine wiring harness on an L-jet system that comes out of the harness at the 12 pin connector end, and connets to the right rear connector in the 4 pin plug at the left rear of the relay board. The other end of this yellow wire connects to the double relay. When the engine is cranked, the fuel pump is energized. If the wire is not there, then the car won't start. The cranking speed of the engine does not create enough air flow to pull the air flow meter off it's stop and engage the fuel pump. After the engine starts, the contacts in the Air flow meter keep the pump running.
If you look at the wiring diagram for the L-jet system:
You see the wire listed as connected on one end to "T4II" and on the other end to pin 86 of the double relay. Start by unhooking the heavy yellow wire at the starter. This should prevent the engine from cranking. Then turn the key to the start position and listen for the fuel pump to run. If it doesn't, unhook the yellow wire from the 4 pin connector in the relay board, and with the key on, feed it power. The fuel pump should run. If it doesn't then you need to check it at the double relay end. Find where the yellow wire goes into the double relay (pin 86) and feed it power. The fuel pump should run. If it doesn't, hook the wire back to the relay board and connect a test light to pin 86 on the double relay. Then turn the key to the start position and make sure the light lights. If it does, replace the double relay.
BEWARE, there are some double relays out there for VWs that have the ground lead in a different location. It is physically interchangable, but the car will not run if it's installed. The difference in the part numbers is one digit, and the parts guys get them mixed up all the time. BTDT.