You guys are getting the wrong idea. This thread is about the heater core issue that only effects the NMS Passat.
As I had the plugged heater core and low heat on the passenger side, I bought a new heater core and clamps and was planning to do this myself. In the end I took my car to the dealer and had the heater core replaced per the procedure outlined in the TSB. What made me change my mind was that I do not know how to flush the Passat system properly. There have been NMS Passat owners who had the heater core replaced per the TSB and they still had to take the car back for another plugged heater core because the system wasn't flushed correctly. I don't know if this was bad luck or dealer tech incompetence. In any case, I'm only paying for this job once and I now have a warranty on the parts & labor if it happens again.
The NMS Passat heater core issue is being cause by excessive solder flux left in the heater core. This is a manufacturing defect. This is not going to happen to any A5 model. Hell, I had to repair the heater box blend doors on my old B4 at 300k miles and I replaced the heater core as a precautionary measure. It was perfectly clean inside.I've been looking around for a how-to on replacing the coolant (for good measure, and to perhaps prevent clogging of the heater core in the first place), or the drain and refill needed before and after the heater core replacement.
I saw the term vacuum fill in another post, and searching for that, I found some commercial tools, as well as a recommendation in TDI 101 (for A5s) to refill by filling the overflow tank and pulling slight vacuum on the upper tank hose.
Assuming this works on the NMS, could one also use this method to cleanly drain a sizable fraction of the coolant on the engine side (as opposed to radiator side) of the thermostat?
Again, you're comparing a NMS Passat with a completely different car. The dash does not have to come apart on the NMS Passat to replace the heater core. It is much easier. For a MK4, it's as complicated as it looks.so, this post seems like a total piece of cake in comparison to this other post http://forums.vwvortex.com/showthread.php?4188858-DIY-MK-IV-Heater-Core-Replacement
so, which is it? I feel like I can do this on my own based on this post, but the linked post makes me feel like I SHOULD take it to a professional!!
As I had the plugged heater core and low heat on the passenger side, I bought a new heater core and clamps and was planning to do this myself. In the end I took my car to the dealer and had the heater core replaced per the procedure outlined in the TSB. What made me change my mind was that I do not know how to flush the Passat system properly. There have been NMS Passat owners who had the heater core replaced per the TSB and they still had to take the car back for another plugged heater core because the system wasn't flushed correctly. I don't know if this was bad luck or dealer tech incompetence. In any case, I'm only paying for this job once and I now have a warranty on the parts & labor if it happens again.
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