I have successfully cleared the blocked aircon drain pipe in my wife’s Alfa 147 (2003 JTD – R/H drive)
- this is what I did:
The diagnosis was a wet sponge against the bulkhead in the passenger footwell causing water to drip down behind the carpet. There are two sponges – the wet one was the right-hand nearest to the center.
Forget about doing anything from inside the car. The aircon unit is bolted to the bulkhead and I think the drain channel is within one of the mouldings and has a spout which pokes through the bulkhead where the wet sponge is.
You need to put the car on ramps and get underneath. There is a cross member at the rear of the engine and where one of the engine mountings bolts onto this (don’t know if this may be different on a petrol engine), if you look up with a torch you should find what I can only describe as a small pair of rubber lips adjacent to the bulkhead. It is difficult to spot at first but keep looking. This is the aircon drain outlet.
Find something about 30cm long that is flexible but has some rigidity which you can poke into the outlet. I used a tie-wrap but I think a bike brake cable sleeve would be ideal. A wire coat hanger is too stiff.
You need to feed the poker into the outlet but then it has to bend through 90 degrees to go through the bulkhead into the aircon unit. You will need to poke it with one hand and put your other hand around the cross member so you can guide it into the outlet. Jiggle it around a bit and hopefully it will find its way through the bulkhead – it will go in about another 4 cm. Move it in and out a little to clear the blockage.
I knew when the blockage was cleared because there was a sudden gush of water – not too much but I had obviously cleared something.
After this I ran the engine with the aircon on and almost immediately I saw water dripping underneath the car. The sponge inside the footwell remained dry.
I removed a couple of bits of trim to get under the carpet where I found a wet, mouldy piece of sound insulation. After about 30 mins with a hair dryer I put everything back together.
I know there is an Alfa modification where a longer outlet pipe is used but I don’t know how this is done. Now I know what to do, I will check the outlet once a year – it only takes a few minutes once you are under the car.
I hope this is of help to those of you with the same problem