The PCV valve wasn’t on the dealership’s list but one of the youtuber’s that I stumbled on while learning how to do all of the maintenance, MrSubaru1387 (https://www.youtube.com/@MrSubaru1387), flagged it as an easy and important item to swap at this mileage. It’s a $15 part and a few minutes of work.

I remember replacing this on my Prelude back in the day.

Here is the pdf guide I made.

Tools and Supplies

Item Notes
Subaru PCV valve Part # 11810AA130
Pliers Not strictly necessary but helped when pulling off the old vacuum hose
Rags / shop towels
RTV Sealant It had some RTV type sealant on the old one so I am including it on the replacement valve. I didn’t see anything specifically for my engine to include the sealant but there were some recalls that required new sealant
Replacement Hose Part #: 99071AD96A
Deep 19mm socket A medium depth would work, but standard will not
3/8" ratchet + extension You’ll need a long extension especially if you dont want to remove the intake

Locating the PCV Valve

You dont need to take anything apart to get to it, but it might be a bit easier if you take the intake off.

These are “after” pics because I am terrible at ‘content creation’ but to give you an idea of where its located:

PCV valve location

Follow that hose off of the throttle body down to the top of the engine:

Hose running from throttle body to PCV valve

Replacement

Replacing it is super simple. Use a deep 19mm socket to take it off. There are some people that clean them with parts cleaner and put them back in but OEM is $15-20 new so thats what I did.

Here is what the old one looked like. You can see the remnants of the RTV they had on it: Old PCV valve with RTV residue

Old PCV valve close-up

As you can see from mine it wasn’t too bad and if I shook it you could still hear the valve moving so it wasn’t gummed up.

Old PCV valve — still moving, not gummed up

I was able to get the hose off without cracking it, but when attempting to put it back on it cracked immemdiately.

Cracked hose after attempting to reinstall

Thats why I highly recommend preemptively buying a replacement hose. That hose specifically seemed more brittle than most of the other hoses I’ve manipulated during these projects.

If your dealership’s parts department is anything like the one near me, if you dont use it, you can return it. So, like I said, its nice to have one handy if it breaks. I struggled to find the part number for this hose online, but the parts department guy new it. Replacement hose

Reinstalling it is as easy as:

  1. Small amount of RTV around the PCV threads
  2. Screw it back it and torque to spec (which was anywhere from 12ft lb to 22ft lb from the articles I read. I used 18 ft lbs)
  3. Connect the new vacuum host

Thats it. Easy Peasy.