volvo 740 ventilation problem

When I step on the gas the ventilation in my Volvo 740 stops. Even when I
turn on the blower and I give a little gas the blower stops.
When the car is running idle or slowing down ther is no problem with the
ventilation.
Who has a solution?

 

It sounds like you have a vacuum leak or a faulty check valve. In my 760
there is a vacuum reservoir with a check valve. Vacuum from the engine is
stored into this reservoir, so there is enough vacuum to operate the
different flappers that divert the air through the console. In reality, I
suspect that the blower does not stop, you may not feel the air coming out
of the vents, because of lack of vacuum to open the flappers in the console.
If you have a hand operated vacuum pump, locate the vacuum source for the
A/C and apply vacuum. It should hold, then operate the levers and locate
either faulty hose, or punctured actuator, or check valve. Good Luck

Arnold

 

Is this car a turbo?