I know this has been DIY'ed before, but this captures some key points in replacing your Air / Oil Separator, and will hopefully help you avoid similar problems and frustrations.
I accessed the bolts and bottom bellows hose from under the car. Remove the right rear wheel. Prop a LED light in the left side of the opening. You only have room to get your right arm in and see what you're doing at the same time. To make more room to work on the bottom hose connection, pop off the wiring connector right in the front of it. Also remove the connector mounting bracket just below that (10mm bolt), and wire it out of the way. I also disconnected the oil filler hose near the intake plenum, to give me just that little bit more room to work.
REMOVING:
- Removing the top hose is easy. Compress the "grips" on both sides and wiggle it off. (I managed to break off the grip ring, I think during my coolant tank replacement gyrations, so be careful.)
- Getting the plastic connector off the middle of the AOS (towards passenger side) was a real pain, as I couldn't really get a good grip on it when accessing from the top or underneath. After struggling with this for a while myself, I had an assistant, working from the top, put pressure on and wiggle the hose towards the passenger side while I worked to compress the release tabs from under the car. Be very careful that you don't break this connector!! Replacing this hose is a serious pain.
- Bottom rubber bellows hose: my new AOS came with a new one, so, because the clamp is so difficult to get to, even with my remote clamp pliers, I just cut the bellows (careful with your knife in there!). Once the AOS was out, getting the remainder out with the remote clamp pliers was much easier.
- Remove the 10mm AOS mounting bolts. From the top, pull the AOS away from the engine to free the nipple going into the engine, and move the entire assembly up and out of the car.
INSTALLING:
I made a huge mistake and tried to re-use the clamp on the bottom bellows. To those that have done it, I bow down to you. I got a replacement screw-type clamp, which made the job MUCH easier. I made sure that the new clamp width was equal to or less than the existing one. Make sure it's stainless, to avoid having it corrode and break. There are clamps available that have rounded edges; consider that too.
- clean up as much as you can in the area. Good practice and helps avoid getting crud into the engine-side nipple. Be careful you don't get crud into the engine openings.
- Once the new AOS is essentially in place, with the nipple ready to go into the engine, put in the two 10mm bolts and tighten (DO NOT OVERTIGHTEN). That will pull the engine nipple in.
- The hose bellows, with the new clamp sitting conveniently up and out of the way, can now be finagled onto its pipe. The clamp can then be easily lowered down and into place. I admit that, with only one hand access, tightening the clamp at first is a bit of a pain, until it's tight enough not to move. But still WAY easier than the original clamp.
- Remount the wiring connector and connector mounting bracket.
- The mid and top hoses can now be pushed on from above. Make sure you hear an audible click to make sure they're properly seated. The mid connector is a bit difficult to push on; I used a pry bar that I VERY CAREFULLY used to get enough pressure to get it to click into place.
DONE.
This is the hole you get to work from under the car, accessed from behind the right rear wheel. It's about 6 inches. I lay on my side and used my right arm.
