1999 4.0 question.

So my friend just a 1999 grand cherokee with the 4.0. The 99' has the coil packs instead of the regular can and rotor, but anyways. It take probably atleast 5 seconds if not more of cranking to get it to start. Once it does start it runs great. Im thinking its a sensor going bad or not adjusted right somehow? Any idea why it would take so long to fire?

Usual reason would be bad fuel line pressure check valve. Unfortunately this is built into the pump so it requires dropping the fuel tank to replace. It is possible to add another check valve into the fuel line. If you search you may find where it has been done. You can check this with a fuel pressure gage hooked to the fuel rail. It may also be helpful (and even diagnostic) to cycle the key to the on position a couple of times before cranking. But the pump will only run 3 seconds without a running signal from the sensors.

x2 with Winterbeater on this, but as it is new to your friend, how about plugs, wires, cap and rotor? Might just be in serious need of some TLC.

Or in the case of coil packs, at least check the plugs.