Chevrolet Tahoe Air Blows Slow Speed From Dash Vents

Question:
1995 Chevy Tahoe 4 door V8. My a/c airflow blows very slow and weak. It is very cold. The blower motor acts if a door inside the dash is not opened all the way or there is some sort of a blockage inside the system. The speed is slow. Is there a common problem on my Tahoe that can cause this problem?

Answer:
Hi JD, I am going to need a little more information. Not sure if you have a fan speed problem or not. Did you replace one of the actuator door motors? Which one. Have you checked the resistor? Any more detailed information you can give me will help me to diagnose your problem.

VISITOR REPLY:
No. All I have changed is the fan motor. It runs all speeds. I removed and switched speeds. I can hear doors moving in dash when i change the settings. It sounds like it is blowing against a closed damper. Very little air flow at vents. I changed the motor hoping to fix it but did not change the air volume.


 

Answer:
Having a little trouble with this one. Checked for service bulletins- none. Asked a couple of the other Tech's. We come up with a few possibilities-
First make sure that the air flow is just not directed to the defrost or floor. That would indicated improper mode door operation and would make it feel less airflow at the vents.

We have had problems with the a/c evaporator core getting plugged with dirt on early to mid 90's cars but not in trucks. What happens is that the evaporator core leaks freon and oil and attracts dirt. The airflow will slowly be reduced over time. The evaporator core is the first thing that the airflow passes through. If there are a lot of leaves or dirt in the area of the wiper arms, then that debre may have gotten into the HVAC case.

If this problem just all of a sudden happened- then by looking at the doors diagram in the manual- there is not one door that can prevent airflow, it would just be directed somewhere else (deforst or floor). It is possible that something is blocking the evaporator core- paper or something. Common problem is it got full of leaves.

Question:
My 2000 Chevy Tahoe has a loud grinding and scraping sound coming from the rear of my truck. It happens when I turn and sometimes when i accelerate or hit potholes in the road. Is this a rear wheel bearing thats gone or is it the u-joints on the driveshaft? It's been doing this for months now. Please help.

Answer:
With the noise doing it in so many different ways, it sounds like a problem inside the rear differential. A u-joint would not have lasted this long and ould have completely broken by now. I suggest having the rear end cover removed and the differential inspected. If there is a lot of metal or the gear oil has a gray color to it, then something inside failed and needs to be repaired. Gray contamination is metal and it will have damaged several components in the rearend such as pinions and gears. A complete overhaul may be needed if this is the case.


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