Fuel Pump not running...

[tchudy]

Just getting done with a rebuild of my 1986 944T engine and wanted to check my fuel pressure before attempting to start. Was wondering if the fuel pump should be running when I turn the key to the "on" position? I have read that the car needs to be cranking over for the pump to turn on. Is that correct?

[zedsn]

Yes, car needs to be cranking for it to come on. Have someone crank the engine over while you put your ear next to the pump or you could just take off the fuel rail end cap with ball bearing (remove coil wire) and put a hose in there with a gallon jug and crank the motor over and see if if it fills up the jug.

[Grandad#3]

The engine must be turning over to excite the DME Relay to tell the DME to run the fuel pump.

Cheers,
Larry

[Arizona_928]

You are correct, you ain't running a carb where you need to fill a bowl before you start turning it over...

[tchudy]

Thanks for the info. All is well with my fuel pump. Good pressure at the fuel rail gauge.

[Freaky]

You don't need to start the car (or even turn the key on) to activate the fuel if you jump pins 30 and 87b on the DME relay socket.

[guru944]

Pix of bypass relay Fuel pump test.
Later...