Does a 2001 7.3 SD have a vacuum pump? If so, what is its' duty cycle?

I have a weird noise when I turn the key to the run no start position (sounds like a pump) which ends a few seconds later with a rattle. The unit this noise is coming from is on the passenger side fender under the hood, just in front of the blower motor. It doesn't sound healthy.

 

Mine does same thing. Not worried about it. Same truck.

 

Yep. bad pump. Worry when you don't hear the sound.

Mark

 

I meant vacuum pump. Yours is fine.

 

yes it has a vacuum pump. mine was making noise but not working right before it totally died. can you control your air flow in the cab? from the floor to defrost? if so its still working.

 

How extensive would it be to replace all the vacuum lines on a sd?? I've got one hanging that used to operate my hubs, my blower is slow to react and sometimes I'll get straight hot air out oft ac then cold conditioned air... Kinda makes me think there is a leak or broken line... Any ideas???? I don't want to just throw a part at it when the one there is working its just not hooked up completely

 

Underhood vac system:

 

Thanks, anyone got a diagram for where it all goes and how it's routed? If not, I'll do my best to trace it

 

ESOF Vac Diagram:



HVAC Vacum Diagram "Manual Operation":



As far as hot and cold running A/C you may need to adjust the A/C cluch air gap. Springerpop's A/C Clutch Air Gap Adjustment

 

I've capped off line going to hubs and still have a vacuum leak. when I put my truck in 4wd my ac blows out of my defroster. Could it be my pvhs or is the leak in a line?

 

I guess what I should be asking is can I remove the pvhs and if so what do I do with the hvac line running from it?

 

The vacuum hub solenoid was leaking on my truck too. Yes, you can remove it. Just plug the line that goes from the solenoid to the vacuum tank.

Chris

 

Vacuum tank, are you talking about the reservoir?

 

My leaks:

1. PVHS (or ESOF module) leaked - new one for about $75 at the stealership.
2. Cracked vac lines on the connector behind the wheel (turn the wheel to get at it without removing or jacking anything). I cut about 1 1/2 inches off the end of the vac tubing to the hub. Re-install freshly-trimmed end and have a celebratory beverage.

 

Yup, that's what I'm referring to.

Chris