2001 GMC Safari. Changed spark plugs, rotor cap and distributor. Started and ran fine. After 6 or 7 restarts the van died down like it was going to cut off and then ran fine. After shutting it off it won't restart. It cranks, but doesn't start.

you need to change the point distributor , but before that check the cable from coil to your distributor .

Sounds like the ignition module or magnetic pick up. You need to check for ignition spark.

This just happened to my Dad's 1998 GMC Safari...

Firstly...

Check the hard vacuum line as previously noted by others.
If that's ok, then take off the intake pipe and spray brake clean into the throttle body while trying to crank it.

If it starts.. then you have a fuel related issue, if it doesn't start then you have an electrical related issue.

Our van did not start after trying to use brake clean.

Take off the console inside the vehicle's cab and get at the distributor.

Usually people noted that the ICM (ignition control module, inside the distributor) was the main issue here, but on our van, the distributor and wires looked brand new so it was probably recently changed (we got this van 5 months ago), so I assumed the spark plugs were also changed at the same time.

We unplugged the connection from the coil to the distributor, tried to crank it, and no spark was being generated, boom, got a new coil and starts up fine.

Just takes a bit of trial and error.

Yes.But first go ahead and do this, then take your distributor cap off and see where the rotor buttom is pointing, you may have it 180 degrees off. So make sure when you do this that the rotor button points at #1 spark plug wire, when the distributor is fully seated.

go back into the rotor cap and check it for carbon tracking, and check the rotor button for carbon/ melting, its possible the coil. make sure you have good fuel pressure and that it hasnt jumped time.

ignition coil most likely as you have changed all the other/recommend replace ignition coil

P0301 is a DTC code that indicates a misfire to cylinder one. It could be a bad spark plug, spark plug wire, rotor and cap, a dirty fuel injector, or the worst a bad head gasket. Cylinder 1 is the first cylinder on the drivers side, towards the front. Start with the simple and check the spark plug wire and add fuel injector cleaner to the gas tank. Good luck and hope this helps you get you van running 100% soon. If that did not help, then your going to have to do a tune up by replacing the spark plugs, wires and rotor and cap. You can get all the parts you need at Auto Zone and they can give you the step by step to get the job done with common tools in under 2 hours of your time. Keep me posted, be glad to know you got your van running 100% again soon.

Have you checked that your coil is grounded?

If ignition and spark seem to be ok, it's time to look at your fuel system. When you say "turns off", if all electrical power seems OK, check the fuel pressure for faulty pump, plugged filter or faulty regulator.

have you ever had a tune up on this van such as plugs, wires, cap ,rotor