M30 Crank, No-Start Fix: Fuel Supply … Wiring to the In-Line, Main Fuel Pump

When I hot-wire the connection to the in-line, main fuel pump, the pump runs. Otherwise, it doesn’t. This tells me that the car’s wiring is not bringing “negative” to the pump via the black wire, or it is not bringing “positive” to the pump via the green wire, or both.

So, the next step is for me to go check that. The methodical way would be to suspect that the negative connection is good, which I could do my running a loooong wire from the positive terminal of the car’s main battery to the green wire on the fuel pump. If it runs, that tells me the negative (black) cable is doing its job, and the positive one isn’t.

I’m inclined to skip this step and see if I can find an easy fix first.

I read up on the fuses, and fuse number 11 is a light blue, 15A fuse that protects the fuel supply. Fuse number 1 is nearest to the rear of the engine. So, I pull fuse number 11 … and drop it in the innards of the car’s engine compartment. Dangit.

I stick a test light in the fuse hole, upright, and I crank the engine. Aha! The light energizes. Next, I replace the fuse, and crank the car. Vroom. 🙂 It starts, it runs. Problem solved. Yay!

I’m guessing that the fuel pump self-destructed, and that drew a lot of current, and in turn that blew the fuel pump fuse. So, it was the classic problem of two separate things being wrong and fixing any one of them wouldn’t solve the problem.

Advertisement