Does anyone know how to clear A/C drains?

So today it is very hot and very humid, the Wife tells me that the fan is making some noise. I turn on the car and water drops start coming out of the A/C vents and there is no water under the car. Normally I get the standard puddle of water. So I believe my A/C drains are clogged.

I jacked the car up and have tried to locate the drains to no avail. The TIS does not call it out specifically but in the A/C section makes mention that it drains into the Transmission tunnel under the evaporator cleaning procedure. I took the bottom cover off to check, but no joy.

Anyone have first hand knowledge?

This is the best I can find at the moment. It looks like it is somewhere near the tranny area. I can let mine run tomorrow & see what I can find.

http://bmwfans.info/parts/catalog/E6..._conditioning/

I found this in the M5 Forum. Maybe it will help. look at post #2

See this:

Thanks Gary and Herb, I appreciate you looking up the info!

Originally Posted by boramkiv

See this:

This PDF is exactly what I need, although the list of items you have to remove to get to the drains is insanity! Remove exhaust, drive shaft, transmission mounts.

Why oh why do the BMW engineers make things so difficult? They just couldn't run a hose out the bottom like everyone else, something I could reach to attach compressed air to and give it a quick squirt of air?

Originally Posted by tampamark

Thanks Gary and Herb, I appreciate you looking up the info!



This PDF is exactly what I need, although the list of items you have to remove to get to the drains is insanity! Remove exhaust, drive shaft, transmission mounts.

Why oh why do the BMW engineers make things so difficult? They just couldn't run a hose out the bottom like everyone else, something I could reach to attach compressed air to and give it a quick squirt of air?

I just looked at the PDF. That is INSANE!

I have a thought after reading the PDF file. Remove the fresh air filter like it states, to pour in the water. Instead of making things worse with more water, make a cardboard damper that will fit tight enough allow some type of seal. Once you have the piece of cardboard fitted, make a hole the size of a shop vac hose. Stick the shop vac hose with the cardboard seal that you made, & use the exhaust port from the shop vac. This should force enough air through the ducts to clear the drain, & not damage anything else. This is crude, but should work!

Good Luck!

Originally Posted by HerbP

I have a thought after reading the PDF file. Remove the fresh air filter like it states, to pour in the water. Instead of making things worse with more water, make a cardboard damper that will fit tight enough allow some type of seal. Once you have the piece of cardboard fitted, make a hole the size of a shop vac hose. Stick the shop vac hose with the cardboard seal that you made, & use the exhaust port from the shop vac. This should force enough air through the ducts to clear the drain, & not damage anything else. This is crude, but should work!

Good Luck!

I tried something similar, I closed all the vents on the dash and put the air to max in the hopes it would create a plenum and force the clog out of the drain.

After looking at all the parts on Realoem and TIS it makes me concerned since there are so many servo driven flaps and such in the system. I will approach it cautiously. I have to take my car in for the leaking transmission pan so maybe I will have them look into this also.