heating problem

[joevit]

My 92 ga 2.4l doesn't blow enough heat. I can hear the blower increase in speed when switching from 1-5 but nothing comes out at the floor. Little comes out in defrost and a little more comes out when in vent mode. Air is hot enough but just doesn't blow. Any help would be appreciated now that its single digit temps here in the northeast.

[crazy Jim]

if your vent doors are vacuume operated I'd check the lines for leaks...

[Aki334]

Jim is right if any leaks in vacuum lines develope for the heating part your GA will go into default mode and will automatically blow mostly towards your windshield. I would check those lines around the vacuum modulator you will see those plastic vacuum lines.

[gmtechnician]

Its a good chance the vacuum mode switch went bad. There is a rubber seal between the two split halves. It rotates and opens the port you want to use.
You may still be able to buy just the vacuum valve in your control head. You can also check under the hood and make sure the vacuum line is still hooked on to the engine. There is also a check valve in the vacuum line under the hood on the left side that I've seen plugged up before.

[xeroinfinity]

most of the time when the vacuum mode switch is bad,
the whole head unit needs replaced. Just my

[joevit]

Thanks for the 411. Where is the vacuum modulator located and how do I get to it?

[xeroinfinity]

This link here should help you figure out whats wrong.

Thiers also the control/head unit link on the right