Hi, I have a '96 Collector Edition that in the past year has decided to stop blowing air through the main dash vents, but will still blow air through the top defroster vent and down in the floorboard. I have not charged the A/C with new coolant in a long time, and the blower also does not always come on immediately when I have the A/C on. Sometimes, the car waits until it's been running awhile and then comes on. Other times, the blower comes on when I start the engine. Can anyone shed some wisdom or intelligent guesses on this issue?

I'd appreciate it, it's gonna be a hot summer... again.

Thanks,
Rod

Sounds like a bad HVAC programmer issue, but there could be an electrical problem, such as a loose/bad ground that could cause this. This has been an issue with the automatic climate control systems for a while, but the later cars, such as your '96 should have had all the bugs worked out of it.
Perhaps someone else can narrow down the possibilities...
You should have someone scan the system for codes, and see if there are any that lead to a particular problem/area to check.
You can check for codes by pressing the fan UP and DOWN buttons at the same time, and hold them down for about 5-6 seconds. Watch the  display on the cluster(where the mileage reads, or on the A/C display...I don't remember), and it should show -00. Then press the fan AUTO button. Any trouble codes will show in the LCD display. Check that, and see what codes it has, then post them here...

Welcome to C4VR, tho!!
Adams' Apple2009-05-28 10:22:22

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it should show on the climate control display. if it was me i would have the a/c recharged first and then go from there. on a scanner i have used it even told me the a/c coolant was low. with the computers in the car don't know if low refrigerant would mess with the settings.

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the dynamic duo

c3vr life member #97

[QUOTE=r0dst3r]Hi, I have a '96 Collector Edition that in the past year has decided to stop blowing air through the main dash vents, but will still blow air through the top defroster vent and down in the floorboard. I have not charged the A/C with new coolant in a long time, and the blower also does not always come on immediately when I have the A/C on. Sometimes, the car waits until it's been running awhile and then comes on. Other times, the blower comes on when I start the engine. Can anyone shed some wisdom or intelligent guesses on this issue?

I'd appreciate it, it's gonna be a hot summer... again.

Thanks,
Rod
[/QUOTE]

Vacuum!

I just went through this.

Does you compressor work?...if not, add refrigerant accordingly and that will give cold air.

Make sure all your vacuum lines are connected and the vent door diaphragms have no leaks.

Once the above two are corrected (or were already correct), then go to electrical diagnosing.

My case; I had to shuffle the buttons from defrost, to vents, to recirculate interior to stop the air from coming out of the defroster and floor at all time, when I corrected the nipple on the vacuum door behind the console, all worked perfectly.


GL






Jim

As vette079 indicated it is normal operation for the climate control system to inhibit fan operation until the evaporator cools, this prevents you from getting a blast of hot air in the face, the time before fan start will vary depending on ambient temperature.
If the green LED above the climate control buttons is NOT flashing when the car is running, there are likely no fault codes stored. 
While you could have a more serious problem such the programmer, the fist thing I would inspect is the three port vacuum check valve located under the right side fuel rail cover.  It is common for the ports to break off as they become brittle due to age and temperature, when that happens the system defaults to defrost mode for safety reasons.
The valve, (PN 15733271) is available from the dealer for less than $10,  a universal version can also be found at many parts stores (one way vacuum check valve)
In the pictures below the valve is the black and white plastic piece with three hoses attached, yours may look slightly different. The fuel rail cover is removed by pulling straight up, you can then inspect the valve.