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Old 07-16-2009, 04:19 AM
bananaman bananaman is offline
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Location: bristol, uk
Join Date: Oct 2008
Posts: 58
Mein Auto: '98 528iT
I have a smell when the car initially is started with a/c running, but it rapidly goes away, so I am not too bothered by the problem. However, it's clear that some are greatly troubled. So, I just took a look at mine, partly out of interest. Here's what I found and suggest:

1. The drain tubes run on either side of the transmission (on my auto), towards the rear of the car. They actually run approximately horizontally for about 12" before the end of the tube is gound. On my car, the tubes actually end beyond the rear of the transmission and rest on top of a cross-member of some sort. That's probably why they are difficult to spot. I tried taking pictures, but the're not good pictures.

2. At great risk to health, I decided to see if they were blocked. Rather than poke a rubber pipe with wire etc, I stuffed a plastic tube about 1 inch up the drain, so it sealed nicely. If you try this, it needs to be 13.5mm - 14.0mm OD tube. That fits OK. I then blew down the tube.

3. On the LHS, there was a bubbly gurgling sound, like air bubbling through water and the end of the drain was wet also. On the RHS, the drain appeared dry and there was no bubbling sound, just air flow. Both tubes appeared unobstructed overall. You can actually hear all this inside the car if you get a long anough tube. My doctor assures me that Legionalla clears up quickly and not to worry.

4. Observation: If, like me you park nose down on a slope in your driveway etc, then at the end of a journey, there will be water trapped at the elbow of the horizontal drain, unable to drain away. This could be one source of water accumulation and smell.

5. Suggestion: I assume these drains vent direrctly into the evaporator assembly. So, instead of drilling holes etc, why not shove the disinfectant spray directly up the drain holes from underneath the car? Once you know where they are, they are very easy to access, without lifting the car
08/1998 528i Touring. Automatic, Steptronic
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