Good questions asked so far. In hindsight I probably should have done some more thorough troubleshooting on this forum before committing, making 100% sure I needed to break into the AC system. That said, the car has over 180,000 miles on it and I’ve been putting off replacing that blower motor for years. Now all that I can do is forge ahead, do all this stuff “while I’m in there,” and let this record remain to hopefully help anyone in the future.


This is where I was at when I started work yesterday. Sucks that the dash has to come out for the blower motor, but now that I’m this far I would like to not have to get in here again.


Got the box out and got to work. There was a TON of lube oil that dripped out of the evaporator plumbing. It made a freaking mess. Damn near have to completely disassemble this thing to get the evaporator out. Thankfully the box is very clean inside. Previous owners must have kept the cabin air filter in decent condition.


The hardware securing the plumbing to the evaporator was in bad shape.


New Nissens evaporator prepped to go in. I added the foam around the perimeter myself to try and match the OE unit as much as possible. The unit itself looks damn new identical to the old one; it does not look like it suffers from cost cutting manufacturing. New heater core and expansion valve with pipes are Genuine BMW parts from BMW Northwest.

A nice hiss came out of the evaporator when I went to connect the expansion valve and pipes, so it should be in working condition. The block that passes through the firewall is plugged to keep the system clean.


Took apart the expansion valve. A little gunky; not sure what passes for “clean” this deep into an AC system.

Finished everything off with new sensors, blower motor resistor, and circulation/fresh air door servo motor.

Shout out to tacairlift and their post here: https://xoutpost.com/bmw-sav-forums/...ement-diy.html. This helped me know what to expect getting the dash frame and blend box out.