Won't start

[ADub]

Replacing my first fuel filter. Pass side battery trashed, so I'm going to replace it. Got the filter on, thought Id check for leaks before I went to get a new battery, truck fired right up then died about 5 seconds later. Do I need both batteries to run? The engine wasn't too cold, but its in the 20s outside. I primed the filter before and after I started it. Any suggestions?

[DmaxMaverick]

The number of batteries doesn't matter as long as it starts. They are wired parallel, so the PCM has no way of knowing how many you have.

You still have air in (or getting in) the fuel system. Typical problem is a poorly sealed filter. Loosen it, check the O-ring and retighten. Use a wrench to tighten it. Hand tight won't do in most cases. If you have a leak, you won't find it with the engine running, as the entire fuel system between the tank and fuel pump is under suction. It has no lift pump between the tank and engine mounted fuel pump.

Try bleeding again, and pump up the primer afterward until significant resistance can be felt. The fuel pump is not self priming.

[ADub]

Thanks for the info, that got it

[More Power]

I've run our project Duramax on just the driver's side battery. The starter sucks pretty hard on the remaining battery while cranking though, especially with the long positive battery cable.

Make sure the disconnected pos battery cable can't touch anything. A shorted positive battery cable could be bad - really bad.

MP