I just finished replacing the lower intake gaskets on a 2001 GMC 2500 Savana van with a 5.0 liter engine. Van has 99800 miles and was used for business until about 2014. I bought the van new. After putting it all back together it started up fine. I walk to the front of the van to check for leaks and I hear this, "click" sound. A while later (12-13 seconds) I hear it again. It's coming from the front of the engine. Sort of on the drivers side. I time it for 4-5 minutes and it clicks every 12-13 seconds.
Oil pressure good. Coolant temperature is the same as always. I changed the radiator hoses and the drive belt as well as the two lower intake gaskets, gas line "O" rings and distributor gasket.
I can't fathom what's happening every 12- 13 seconds that is involved. Took the van out for a 30 minute test ride and it was fine.
Suggestions
Thanks
Ron

 

Ac compressor cycling?

 

I'll check tomorrow.
Thanks.

 

does it click even after you turn the van off?
exhaust expanding/contracting?

 

I'm on way out to the van now, but I don't think it clicked when the van was off.

 

It was the A/C. Once I switched it off, the clicking stopped.
I don't know if this is normal or not.
Is it?
There is no clicking with the engine off.

 

probably the normal sound of your compressor cycling on & off

 

The compressor cylcles to move oil around the system. Thats why the ac works on defrost....so it gets used during the winter......normal. Just dont leave it on defrost or defrost/floor all the time. Use floor or vent unless you are trying to defog windows, or use ac for cooling. it wont cycle on off forever.....lol

 

Teamwork... I like to read that a problem or an issue is Solved.

 

The issue I'm having is that I've owned this van for 16 years and don't remember hearing the clicking sound before this. Maybe I never had the A/C or defrost on when I've previously in the engine bay. Appreciate all the help for this. I'll just keep monitoring it and see what happens.