BBi: Running fuel pumps

If you turn the key to "On", wait a few seconds and then "Off" a few times (you will hear the pumps at first) you will build up pressure in the system. Then you should be able to go around and look for leaks. Assuming that everything was reasonably tight to begin with there shouldn't be much to see.

This will run both pumps just long enough to reach operating pressure but should get the job done without unplugging anything. Without cranking the engine, the pumps will only run a couple seconds each time the key is turned.

 

No that isnt the case. On the left fuel distributor there is blue connector that looks like an injector plug. This is the switch for the fuel pumps that only turn on when the air door is depressed by engine vacuum (during cranking). With the key on and the plug disconnected, both pumps will energize and run as long as the key is on. I wouldnt bother running them individually. You'll also notice the right distributor has a switch but no plug connected to it, this is because they just use one trigger to turn on both pumps. Its a safety measure to shut off the pumps in an accident when the engine shuts off. Another step you can take while the pumps are running is to lightly press the air door down with your finger which will send fuel to the injectors but dont do this too long or too often as you will start dumping fuel into the ports and flood it. If you just run the pumps, do the visual then start the engine, that will be good enough at which time you can look at the injector lines while it idles.

 

Alternatively, if you do want to run only one fuel pump at a time, unplug the corresponding fuel pump relay and add a jumper between the 30 terminal and 87 terminal in the female relay socket per the jpeg -- the fuel pump will run even with the key "off":
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