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Mon Jul 12, 2004 8:51 pm

I just finished putting all new tin work and all new exhaust on my 76' super beetle. Now that the engine is back in it starts and dies almost immediately. Isn't this a common sign of it not getting gas? There is gas pressure did I mix up the two feed lines comming from the tank to the engine? Can anybody tell me which is which. Has this ever happened to anyone else? This beetle is Fuel injected.

Tue Jul 13, 2004 8:58 pm

Check all the vacuum lines.

-jeffrey

Tue Jul 13, 2004 10:43 pm

If you cross the fuel lines, you can restrict gas flow, depending on the condition of the fuel pressure regulator. With any amount of gas in the tank and the key turned off, the "return line" will produce an unimpeded stream of fuel when tipped below the plane of the gas tank. This one should connect to the output of the fuel pressure regulator on the right side tin. The line which produces a momentary stream of fuel when tipped down is the "supply line". Attach it to the injector fuel rail on the left side of the engine. If, however, you are meauring fuel pressure on the rails in the engine compartment, you have the lines connected correctly and you need to look elsewhere, like the decel valve hoses and, as pointed out by Jeffrey, all of the vaccum lines. If these all check out, inspect the air flow meter cut-off switch. If it is not working, you will get a momentary burst of gas pressure to start the engine, but it will cut off the pump power when the air flap deflects.

Wed Jul 14, 2004 11:50 am

I have linked the problem to the injectors. None of them are getting power. Well they are all getting power when the key is turned but the computer is not giving them the ground they need to fire. Why me?

Thu Jul 15, 2004 9:05 pm

The FI used on Beetles has an electric pump. It gets its 12V from two sources. The first source is the crank position of the ignition switch. The second is from the air flow meter on the engine. The crank position energizes the pump so the engine can start. Then when you let go of the key, theoretically the engine is running and the flapper is open. When the flapper is open it delivers 12V to the pump.

You can test the switch in the flapper by taking the air cleaner off and stick a long screwdriver in far enough to open the flapper. Then turn the key to the run position while listening for the pump. If this is the cause, you've narrowed your search. This happened to me on my 75. The problem with my car was the wiring harness from the FI box to the air flow meter as it passed over the fan shroud had rubbed right through the wires for the switch to activate the pump.