Engine won't start

Just bought a '99 Suburban with 5.7 Vortec. Ran great every time before purchasing. Brought it home and it sat for a week and then battery died. (Will chase leak later) Tried jumping but we cannot seam to get fuel into throttle body. We can dump fuel down butterfly and engine will run until fuel is burned out. We have changed fuel filter and tested PSI of fuel pump at 64. Pulled wires and have spark on plugs. It does have an after market alarm and thought maybe once battery was replaced it would reset and maybe that was preventing our starting. (Only have one key to unlock and no fob or anything.) Kind of at a loss as to what needs to be done next. Can I test the modular (computer) somehow? Anything else that may prevent fuel from getting to spark plugs? (Plugs are dry when we pull them out to check them.)

I don't know much about cars, but have friends who have given different suggestions on what to try. Would appreciate any other suggestions.

Update: We pulled all the mess of wires for the after market alarm/remote starter/key-less entry (had to be 30+ wires) from under the dash. Interesting how some of the wires were spliced together. Reconnected wires as appropriate and viola!

Update: We pulled all the mess of wires for the after market alarm/remote starter/key-less entry (had to be 30+ wires) from under the dash. Interesting how some of the wires were spliced together. Reconnected wires as appropriate and viola!

thanks for posting your findings.

I was gonna suggest you get rid of that alarm security system ..

your findings of the poor install is why many have suffered from these issues...........