vacume pump

[mncguy]

is the a/c linked to the vacume pump,the a/c blows from demist to face depending on acceleration or throttle load.does the flaps inside the cabin run off the vacume pump,have i got a cracked line somewhere which is causing a air leak which then works at higher revs.has just started to dump black smoke under hard throttle

[Robyn]

The turbo is controlled by the Vacuum pump.
Check the vacuum pump for function at the pump (26" HG and steady) and then work out to the controls and the wastegate actuator.

The HVAC is not controlled by vacuum (At least not the rigs sold in the States)
All the rigs sold here since the late 80's (92 in the Burbs) have had electric servo controled HVAC systems.

Check it out and let us know

Robyn

[93GMCSierra]

Does that depend on if its a 1500, or 2500?
I saw a 1500 pickup with egr and what sure seemed like vacuum controlled HVAC.

[mncguy]

its a 2500,these burbs that were for the australia market had a right hand drive blazer dash stretched to fit, the stretch being a 6 inch piece put on the left hand side of the dash,so did the blazers run a vacume control.truck is going in for a code read and other bits and pieces on friday,only have to drive 400ks to get this done

[Robyn]

With export rigs its hard to say exactly what the factory installed.

Check the vacuum pump and if its bad, fix it and the issue will probably go away.

Be sure the vacuum lines are good too. Here in the states there are mostly a hard plastic but ???????? Rubber vacuum hose will work fine.

Best

Robyn

[mncguy]

mmmmmm not good,diaphrame has a hole in it,does anyone know the part numbers or numbers associated with this,have been quoted $410 au so any help from across the pond would be appreciated

[mncguy]

all is good,found a replacement one from a wrecker,breaker,salvage yard and was only 1700k,s away,thought was going to be a hard job to replace but by the time you get rid of the fan shroud and fan itself it was a really easy job