VBacuume diagnostics

[Aramis001]

Earlier today, I realized I have no brakes!. The car was fine for a minute, next minute I had to push the BRK pedal with two feet,, I also noticed late shifting, climate control problem (no control on the air flow) and engine shut off issues(had to use the emergency engine shot down). I assume this is vacuum related. I however don't know if it has to do with the main vacuum system or a leak, how can I diagnose the problem?
Thanks for replies

[tangofox007]

Sounds like a fairly catastrophic vacuum failure. What would be the year and model of the offending vehicle?

[rg2098]

An extremely catastrophic vacuum leak like that can only be the pump going south.

[tangofox007]

Originally Posted by rg2098

An extremely catastrophic vacuum leak like that can only be the pump going south.

I have seen the check valve on the pump fail and produce similar symptoms. I would start by checking the check valve.

[rg2098]

I'm sorry, I was implying the pump or something on the pump was bad, not a leak or another failed component somewhere else in the system.

[Aramis001]

Excelent response to my question. I thank you all.
My car is a1986 300SD with over 300K miles on it. looks like i will need to change my vac system. I am concidering a 1995 , 350 SD large body. Any of you have positive or negative exoerince with this vehicle, What kind of maintnance cost i may expect. With the 300SD i currently have i had vertualy very little maintnace cost.

Thanks

[Alan Hamm]

I didn't think they made the SD's in 1986. Wasn't it SDL's only in 86 and 87?

[Aramis001]

It is 300SD, very nice car.