DW300 pump failure :(


Didn’t make it to the track this weekend like I was hoping. I wanted to make a few passes and claim one of the Grimmspeed TMIC bounties for running a 10 second pass. Lets just say that friday was an interesting car day. I was pulling some logs for some final touchups on the tune and out of nowhere the AFR began to spike to 14+. Fuel pressure was down almost 20psi! I cranked up the FPR and no change…figured maybe its a bad Aeromotive FPR. I limped home and didn’t drive it.

I pulled the Aeromotive FPR today to check it out, as everything else seems fine. Disassembled it and it seemed brand new still.

Put it back in and it returned to idle at 35psi (like it was Friday night). What the heck is going on?

I sit on it for the day and go to start it this afternoon. Fuel pressure dropped to 8psi…WTF?! I then realized there was no more loud DW300 pump noise…both of them were not turning on. Checked all the fuses. Pumps are dead. Go figure, the one time I give DW a try (when a lot of DW300 pumps have failed on E85). The poor Walbro 255 is trying its best to create pressure through the dead pumps and feed the engine. At least it is not dead.

I drained the tank, pulled the pumps, and rewired in a single Walbro 460 and things are back to normal. This time, with a single pump, if it dies, it will be immediately noticeable vs a dual pump setup could have one failure and still be somewhat functioning. Car is running awesome now!