[HANDYMAN SAM]

I Just Replace My Vacuum Pump On My 2000 F-350 It Works Great Shuts Off Like It Should Except When The Heater Selector Is In The Off Position The It Comes On And Runs Costantly
Thanks Scott

 

[fulltimer50]

Welcome to the site!!
Sounds like you have a vacuum leak. Turn the truck off. Turn the key back on but dont start. Listen for a hiss under the dash.
Or just leave the heater selector on or in vent.

 

[DieselDeaf]

You need to find out what is leaking, not sure if you are gonna hear it unless you have super sensitive hearing. If you have a mitivac you can check each component separately and might also want to pull the control at the dash and do some checking there. There are three or four vacuum pods that can leak but you also need to check the lines and the vacuum reservoir under the hood.

I have a work truck that had been eating vacuum pumps for several years now and I finally took the time to fix it. The pumps are expensive and don't last very long when running nonstop. On mine it was a bad pod down at the passenger footwell.

 

[HANDYMAN SAM]

Checked for leaks

I have checked for leaks the hubs are all sealed. When I turn heater selector to any position except off the pump stops like it should when I turn the heater selector it to the off position the vacuum pump turns on and stays running is there a pod for the heater that is only active when the heater is off. I have pulled the selector out and checked for leaks but havent forund any on pods or lines leaking.

 

[fulltimer50]

It can be the selector itself.

 

[HANDYMAN SAM]

Thanks For All Your Inputs

After Trial And Error We Eleminated Each Pod Until We Found The Pod That Was Faulty
Thanks Guys