Odd Starting Problem with GMC Safari

My 2005 GMC Safari has recurring starting problem that doesn’t occur after the vehicle has been shut down for longer than 6 hours and shorter than 30 minutes. However, when the van is off for about 2 hours, it frequently doesn’t start back up. When I turn the key I can hear the fuel pump, but nothing else. And after a number of times turning the key, sometimes as many as 30, the van just starts back up as if nothing was wrong with it. Is there a timer type switch that may be causing this problem?

You turn the key and the engine does not crank?

Yes. That’s right. No clicking, nothing. Just the whirr of the fuel pump.

We must see if a signal is getting down to the starter. Let me ask first does the van have a aftermarket alarm or remote starter now or has it ever had one?

Can you influence cranking (thats what we we call this, not starting) by moving the gear selector while holding the key to start? (I am thinking of a neutral safety switch issue).

All electrical problems start at the battery,how does yours look? I would like you to remove the cables,inspect them,clean them,and remove your battery and have it load tested,I don’t know if this is possible for you to do but it is my wish.

Next I would like for you to get under the car and inspect the wiring at the starter. Are all wires tight? the big one (this has voltage at it be careful if you have a tool down next to it and the battery is connected) has a bad habit of comming loose.

Next with everything hooked up and the van in failure mode (Key held to start) I would like you to measure the voltage on the purple wire at the solenoid (I dont know if this is going to be possible for you to do)

If all these checks do not reveal any problem then we are dealing with a ignition switch problem.

I am discounting a ground problem for now but a least you can trace the heavy black cable from the battery to its mounting point and check if it is tight.

Let me/us know if you can organize any of these checks. Feel free to modify my battery load test directions to suit your circumstances, but do the neutral safety switch first before disabling anything and make sure about your report on previous or current alarm installation.

Thank you. I appreciate the direction very much. I will report back when the cause is found. It may take a couple of days. I do not now or have ever had a remote starter or aftermarket car alarm.