I have a 2000 escalade with a 350. It turns and turns but won't fire up. This all started after a rain, and has only gotten more consistent not starting. If I ran it everyday it would stay running but now that is not the case. It also backfires after I stop cranking it like its trying to barely run but won't. I changed out the dist cap. I am now considering changing the plastic rotor disc inside and maybe even the part that is wired up underneath that. "dont know what its called but it unplugs from wiring" and I'm also considering changing the plug wires. However, just changing parts out hoping to fix it is not troubleshooting and will get expensive. Plus how will I know what fixed it unless I do one at a time... I won't. Is there a fuel pump module problem on this make and model like on the ford I read about?

I suspect the Ignition Control Module (ICM) is bad. Easy to replace.