In the spring, I installed a Denso Supra TT fuel pump in my B2200, it was a drop in install, it was identical to the stock pump in connectors, size, etc... I noticed right away that my aftermarket fuel pump cutoff switch which runs inline on the power wire was very hot due to the increased power draw of the pump, so I upgraded the stock wiring. I ran a new 14AWG wiring from the battery to a new relay and to the pump, I also upgraded the ground wire from the pump to the chassis. I used the old wiring from the fuel pump relay to the pump to enable the new relay. I ran like this all summer, and about a month ago, I noticed my power wire coming from my battery was getting discolored from heat at the spade connector crimp only, I am running a 20A fuse on this circuit. I checked my other connection on the back of the cab which is the same spade crimp connector, and it looked the same, the wire felt warm, not hot, when the engine was running. Looking online, it seems this Supra TT pump can draw lots of amperage at high pressure and flow, upwards of 30 amps, I upgraded to 10AWG wire from the battery all the way to the pump itself and same with the ground. I am using a ratcheting crimping tool for the connectors, we used them at a previous job I was at and this style is CSA certified, not a cheap crimper that is used in the wiring kits that you buy.

This worked fine for a week, then one day, my pump did not come on when I turned the ignition on. The next day, it worked fine, then the next day, again it did not come on, so I checked with a multimeter, and I am getting power to the pump. Both days the pump did not work it was around -10ēC out, and when it did work it was about -5ēC.

Is this a sign that my pump is dying, or is there another issue here? The pump is not that old, and all summer, I did not notice the wiring being discolored, it seems like it happened recently, is it possible that my pump is burning out, and drawing more amperage? When the pump does turn on, the truck runs fine, but I have not driven more than around the block in case the pump quits while driving.

 

In my RX-7 the bulkhead connector would burn where it passes thru into the tank.
I upgraded to the racetronix one for $49.

 

The Racetronics product is great, works perfect.