Blend Door Actuator

Where is the blend door actuator and how do I fix a vacuum leak??

what year is your Lumina?

1996

I assume your car doesn't switch from floor to vent to defrost, etc... The vacuum that supplies the heater valves comes off the throttle body. the mode valve actuator is up under the dash, to the left of the console, toward the front of the car. The defroster actuatator is right near it more toward the rear of the car.

when you say to the left under the dash - do you mean under the glove box or the steering wheel?

just to the drivers side of the center console, but up high under the dash