Vacuum Pump is vibrating and runs constantly

[Kamper Dave]

2004. 5 Dodge Ram 2500 4x4 with 5. 9 Cummins.

The vacuum pump near the firewall on the passengers’ side of the engine compartment is vibrating constantly. If it shuts off at all it is only for 15 seconds and it starts to run again.

Is this pump easy to replace?

What is it supplying vacuum to?

Thank you in advance for your answers………………… Kamper Dave

 

[MarkEkberg]

Guessing you might have a vacuum leak? Have seen them fail on other trucks, but not usually.

 

[Bill Stockard]

2004. 5 Dodge Ram 2500 4x4 with 5. 9 Cummins.

The vacuum pump near the firewall on the passengers’ side of the engine compartment is vibrating constantly. If it shuts off at all it is only for 15 seconds and it starts to run again.

Is this pump easy to replace?

What is it supplying vacuum to?

Thank you in advance for your answers………………… Kamper Dave

As posted above, you probably have a vacuum leak either in the vacuum hose or in the Cruise Control servo. Pinch the vacuum hose closed next to the pump and see if it stops rapidly cycling on and off. Also check the vacuum hose near the Cruise Control servo. The electric vacuum pump furnishes vacuum to the servo in the Cruise Control unit usually located near/under the driver side battery. The electric vacuum pump is relatively easy to replace, but costs $$$.



Bill

 

[Kamper Dave]

Thank you for your responses. I'll check it out.
I did ask the Dodge Dealer to check on it, his response when I returned: "I don't know what it was but it quit after a while. " I think I need a new place repairman.

 

[JWiegel]

04. 5 vacume pumps just run mostly HVAC having no mechanical APPS there is no cruise servo its controlled thru the ECM its full electric APPS.

 

[Lordsman]

I had a 04. 5 with an auto transmission & it had an electric vacuum pump. Cruise would not work correctly either. Found a hose rubbed out on the other side by the drivers side battery. Splice repair fixed it and vac. pump would cycle off properly.

 

[cerberusiam]

04. 5 vacume pumps just run mostly HVAC having no mechanical APPS there is no cruise servo its controlled thru the ECM its full electric APPS.

None of 3rd gen trucks use vacuum on the heater\AC controls, they are all eletrical motors.

The 03-04 trucks used the vacuum pumps for the cruise control only. Speed control was in the computer and did not require vacuum.

Yes, the pumps can go bad or the hose will rub a hole and they cycle all the time. Need to do as suggested, trace the hose and start crimping to see if there is a hole somewhere.

 

[Kamper Dave]

THANKS AGAIN!
I opened the hood and turned the ignition key to on. I used hemostats to pinch the rubber tubing near the running vacuum pump. It stopped running as long as the line was pinched.
I disconnected the rubber tube at the filter / check valve and blew into the tube to hear the leak. The leak was near the firewall and before the tee fitting that routes tubing through the firewall and into the cab. I cut a small patch of 3M electrical tape to cover the hole and wrapped that with more tape.
All is well.