Fuel pump failure?

[jangell]

I ran out to do some errands today, and my car died just as I pulled into a parking space. When I got back out, it wouldn't start. It would crank and catch, and then promptly stall. I soon found that I had zero fuel pressure, thanks to the fuel pressure gauge I'd installed in the engine compartment.

I have DMCH's fuel pump/sender combo. The car has only been on the road for seven months, and the pump was used for testing before that, and has been installed soon after I bought it in 2013 (the car was not operational when the pump was installed, as I was doing an engine swap at the time). However, the pump has worked fine until now.

After some false leads, I found that the main fuel relay does have power. The relay is being energized by MegaSquirt (in a 3.0L EFI conversion, so no RPM relay). Once I finally remembered about the test mode in TunerStudio, I turned the pump on and confirmed that I'm getting 12v all the way to the pump connector, and that I'm getting ground from the other side of the connector that runs to the inertia switch. I also opened the tank and confirmed there was fuel in there (about half filled).

So, I'm fairly confident that everything is working up to the pump, and that the failure is at the pump or the white control box that feeds into the pump. The fuel gauge still moves when I try to turn on the car, so I'm thinking it's the pump itself, but I' m not totally sure.

delorean.com mentions that individual parts are available separately for this pump/sender combo, but how would I go about figuring out which part has failed? I'm well past the 6 month warranty, so getting just the part I need would be ideal.

Thanks!

-- Joe

[Patrick C]

My DMCH combo pump failed last year and wasn’t making enough pressure.

[CFI]

Sound like the pump. The white control box you mentioned is the microprocessor for the sending unit. I believe it adds a correction value in order for your fuel gauge to be more accurate.

[David T]

Once you pull the pump you can try putting 12 volts and ground directly to the pump and see what happens. Maybe a broken wire? It is possible the pump is dead.

[jangell]

I pulled the pump this morning and applied 12v and ground to the connector. Instead of whirring like a motor, it clicks like a solenoid. I'm guessing that means it's dead.

At least my filter looks reasonably clean, with just a bit of captured debris.

IMG_1918.jpg

Thanks!

-- Joe

[David T]

If it clicks it means the power is getting into the pump but it won't turn. As "Bones" would say in Star Trek, "It's dead Jim".

[Josh]

I had my dmch integrated pump/sender fail on me fairly quickly as well.

That filter looks very good

[opethmike]

The DMC-H fuel pump is dumb. You're dumb for using it. DeLoreans are dumb.

That filter is NOT dumb.

[jangell]

I have a replacement pump part on the way. I'm sure it'll work fine and I'll never have any problems ever again.

-- Joe

[CFI]

I pulled the pump this morning and applied 12v and ground to the connector. Instead of whirring like a motor, it clicks like a solenoid. I'm guessing that means it's dead.

At least my filter looks reasonably clean, with just a bit of captured debris.

IMG_1918.jpg

Thanks!

-- Joe

How old was the pump? How many miles on it?