No vacum

[tennessebiod]

Greetings
I am a new member and a new diesel owner. The cruise control doesn't work on my Sub and the climate control sytem only produces airflow at my feet.Checking the vacum pump there seems to be no vacum - at idle the plug into the pump shows 4.17 volts -does this pump use electricity to produce vacum or engine pressure-pardon my ignorance - continuity testing of the terminals on the pump 1.7 on 2000k ohm scale.
Thanks for any help.
p.s any recommendation on better shop manual I have a Chilton and it is pathetic.

[86burb]

Sounds like a defective vacuum pump. The vacuum pump is either gear driven or belt drive. With the engine running the pump should reach at least 20 to 21 in-hg within 30sec. Check all vacuum controlled accessories and connections. The Haynes diesel repair guide has a decent amount of info (ISBN 1 56392 188 X), cheap and easy to aquire. This is an excellant site/forum with lots of helpful info.