After replacing the radiator the A/C is not as cool and blows air out of all the vents

1999 PONTIAC GRAND PRIX
155,000 MILES • 3.8L • 6 CYL • 2WD • AUTOMATIC
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99GTP
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I just changed the radiator in my car listed above GTP and my A/C was running fine before and now it is blowing air through all the vents; meaning the defrost vent, the floor vent and the front vents. it’s weak as well. Plus the A/C is not as cold as it use to be.I was wondering if I mess something up when I unplugged my PCM before I unplugged my battery? It’s weird because I cannot change the mode to have it blowing just from the front vents. Please help.
May 12, 2020 at 3:14 PM
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ASEMASTER6371
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Good evening,

The actuators are controlled by vacuum. Go over all your work for the radiator and see if you disturbed something in the vacuum system on the engine.

I attached a vacuum diagram for you to view. Check the source tank for the main vacuum into the control head.

I attached the location of the tank for you. With the engine running, you should have vacuum on one of the hoses from the motor.

Roy

1. Remove the right and left instrument panel insulators.
2. Disconnect the vacuum hoses from the vacuum tank.


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3. Remove the mounting screws that secure the vacuum tank to the blower case.
4. Remove the tank.
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May 12, 2020 at 3:58 PM
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99GTP
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Will the vacuum line run right there by the battery? Because I did take the battery out and it’s holding plate. I probably bolted it back on top of the vacuum line.
May 12, 2020 at 8:45 PM
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ASEMASTER6371
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I do not have a route diagram for the vacuum line but it is possible.

I would remove the battery again just to be sure you did not pinch it at the bottom.

Roy
May 13, 2020 at 3:21 AM
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99GTP
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Thank you so much my brother!! I found the vacuum line that snapped. Much is very appreciated for the help for saving me a lot of money I do not have. And to think I was going to buy an actuator. You are a natural born champion my brother! Thank you and God Bless you.
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May 13, 2020 at 5:43 AM
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ASEMASTER6371
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You are welcome.

Thank you for the kind words.

Always glad to help.

Roy
May 13, 2020 at 5:48 AM
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FRESHLIKE78
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How did you fix the line? mine had did the same thing and air is blowing through all vents as well.
Oct 20, 2020 at 12:39 PM
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ASEMASTER6371
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You can use a larger vacuum line over to broken portion to join them together.

Can you attach a picture of the line you have so I can see it?

Roy
Oct 20, 2020 at 4:51 PM