2000 Express - Fuel Pressure Problems

I have to cycle my ignition on and off 4 or 5 times to get my van to start up. If I use starting fluid it fires right up. I have to go purchase a fuel pressure gage to some testing, but my question is how do you know if the fuel pressure regulator or fuel pump is the cause of fuel pressure not building up?
How do you test the fuel pressure regulator?

Go easy on the starting fluid or you may blow the dip stick threw the hood.
Only use carb cleaner as a starting aid.

What engine and what size van?

Guide lines for checking fuel pump and regulator and fuel pressure.

The only true test on a fuel pump is to check the direct fuel pressure from fuel pump.
A quick test is to block off the return line and see if fuel pressure comes up to 75-85 lbs.
But do not run the pump at full pressure very long.
Also when testing fuel pump and pressure you need to tape a gauge to outside windshield or outside mirror and drive it on the road for 20 -30 minutes
until the pump gets has run a while to check for a pump fading out after hot.

Hard to start cold or hot and fuel pressure testing guide lines.
Check cold start fuel pressure.
Check engine running fuel pressure.
Check engine running on the road fuel pressure.
Then shut it off and watch for fast leak down.
Pinch off at rubber part or block off return line and check full pressure.
If pump has full pressure with return line blocked and low pressure without it blocked most usually the fuel pressure regulator is leaking or not holding pressure.
Later V6 and V8 gm engines should have 60-66 fuel pressure.
Cold start should be 64-65 lbs of pressure.
If you do not have full fuel pressure on a cold start the injectors will not squirt fuel.
Do not leave home without it.
Engine running should be 60-66 lbs pressure depending on engine load.
Full pressure with return pinched off should be 75-85 or more.
And if it has a fast leak down after shut off you have a leak in system.
Post back fuel pressure readings.

OP,
Starting fluid will also help to compensate for weak spark. How many miles on the plugs, etc?

The Van is a 1500 w/5.0 engine.
At 102000 miles I gave it a tune up. (plugs,wires cap & rotor)
at About 114000 miles it started acting up with a misfire.
With the dog house off I noticed my wires were arcing in a couple of areas.
Did another tune up but didn't replace the plugs. I did put a new coil on it at this time.

Van now has 126000 miles on it. The starting problem has gotten progressively worse thru the summer.

I have the dog house off and ran it at night. It appears that all the plug wires on the drivers side have visible current running thru them(hope that's a good discription) when you accelerate, no arcing to metal parts just visible current. Could the wires be the problem? If so why would it start instantly with starting fluid and run flawlessly, no miss, hesitation,etc..). Put Autolite professional grade wires on it when I did the second tune up. Do these vans eat plug wires?

Plan to buy a pressure gage this weekend to test fuel pressure.

Sorry this post seems to be rambling but this really has me stumped

As in post 2.
Read it and check that fuel pressure.
If the fuel pressure is not at 65 lbs on a cold start the injectors wiil not squirt.
No fuel no start.
Get that fuel pressure gauge and post back pressures readings as outlined in post 2.

Did you put the wires in the wire guides the way they were when new? This HAS TO be done.