[Northerner]

2007 Rabbit, 5 cylinder, 2.5 L.

I,ve had two blowers put in and still having same problem. The blower fans makes all the sounds from fan speed 1 through 4. However, the air barely comes out of any of the vents. When the air is not coming out the vents the blower fan noise is near the cabin filter, when things are working the blower fan noise is nearer the vents. The mechanic used a camera and the vents are clear and the flap inside is operational. This is an intermittent problem. Being winter I need to be able to clear the windshield as well as have some cabin heat. The cabin filter was also replaced.

 

[briano1234]

Intermittents are very hard to find, that is the sad truth.
I would start with asking if you have a/c.
The difference is electrical or mechanical.
I would think that you have an issue with a servo motor or a connection to the Defrost servo.
Reseating the connectors and ensuring that you have a good ground and power to it are essential.

Sure they are working when the mech is there as that is Murphy's law. (Murphy's Postulate is that a Computer or Machine will function to manufacturers specifications as long as a repairman is present.)

While I don't know the specifics on the newer models, I do know that the defrost door is where the air is shuttled between the center vents and the defrost.
I also know that on a latter a4 that my niece had, the oil cooler if leaking can gell the a/f and cause the heater core to get plugged up.

So you might want to inspect the coolant system, and have it tested for oil intermix. Also since the heater core in the newer models is the highest point it is subject to an air pocket, and you may just need to bleed it if the a/f to oil has no intermix.

 

[Northerner]

I do not have AC.

 

[briano1234]

I do not have AC.

Then you usually don't have servo motors, but then you have Cables that control the flappers.
So I would look into that as well, as seeing if you have a air-bubble in your heater core that is preventing it from getting hot.

 

[Northerner]

Thank you. I’ll run your thoughts past my mechanic.