Friends,

I am building a Silverado for a gentleman. I used a racetronix hot wire kit for two pumps that has a Hobbs for the second pump. The pump plugs in and gets power to the relays via the alternator. The issue is that this was a returnless system but I did not see a FPCM mounted under the bed. Where else could the controller be? Single cab 04 Silverado. It doesn’t have a communication loss DTC either. I’m looking to bypass whatever the control function the truck has as it is a return style fuel system now. Any suggestions on how to get that accomplished would be great!

 

There is no fpcm. The system has a built in regulator/filter setup at the tank. The pump runs 100% all the time. If you have removed this stuff and plumbed in aftermarket pumps and a return system, you will have to update the fuel injector tables in the tune to reflect that type of system. You would just use the factory fuel pump power wire to activate your relay to turn on the primary pump.

 

The regulator is built into the factory pump.

You will need to add a regulator and return line to the tank

 

Thanks for all the help! now for the next issue. I tied into the fuel pump wire coming from the pcm to trigger the relay. I did not clip it. the fuel pump will not turn off with the key. The racetronix system still uses the original plug for the fuel level etc. Any ideas as to why the pump would not turn off?

 

It runs all the time with the battery connected?

 

When I go key on the fuel pump will go hot and continue to run until i pull the fuse. I cut the wire running to the fuse panel out and now the fuel pump will not come on at all.

 

Not familiar with the racetronix kit... but the pcm will supply voltage to control the relay from C2 (green) pin 9 dark green/white wire.

Wire your relay accordingly