11th Gen Civic Forum banner

Oil catch can and K&N air filter

3467 Views 61 Replies 8 Participants Last post by  iLLuSiVe
Installed a mishimoto oil catch can and a K&N filter. I will see how much oil it catches on the first oil change. Also the filter made a tiny improvement made the turbo a hair louder. Way better than stock. Worth the $40.
Grille Rectangle Font Material property Gas

Automotive tire Motor vehicle Vehicle Automotive design Automotive lighting

Hood Vehicle Automotive tire Motor vehicle Automotive exterior
See less See more
  • Like
Reactions: 3
1 - 20 of 62 Posts
How is the catch-can doing?
Haven’t opened it yet. Going to when I do the oil change, that will be soon. I’ll post pictures of it and an update.
Thank you! I just got a cheapie baffled can like I have in my MX-5 and going to install this weekend, I didn't want to "mod" the car but after some research it just seemed like a good idea for Turbo DI engines especially
  • Like
Reactions: 1
Appreciate the follow-up! So is that a lot and would you consider this worthwhile? Not as familiar with catch cans.
I wouldn't say that's a lot, but seems about right for what I'd expect as blow-by. Catch can is a worthwhile mod for sure, especially for these Direct Injected Turbo engines. I'll link to a few good videos below about why this is worth the investment, even for a stock car. For a port injected engine, its not as critical because anything that gets on the intake valves through the PCV system is constantly being washed off with fuel, on a DI engine it just builds up over time. The way I see it, even trapping a tablespoon of this stuff every oil change is a win. Why don't stock cars have catch-cans? Because nobody would empty them. My turbo Miata had one from factory but it was designed to catch blow-by and then drain it back into the oil pan, which created a host of other issues

  • Like
Reactions: 3
Very happy with the placement of the Mishimoto can, very OEM looking and plenty of room to unscrew it for emptying
Grille Vehicle Automotive tire Hood Automotive tail & brake light
See less See more
  • Like
Reactions: 2
How do you think removal would be with a strut bar above it?
More of a pain in the butt for sure. Do you already have a bar in there?
Yes, I do
If I had to make my choice I’d ditch the bar for the can, or just work around it. Those bars don’t do much anyway, the firewall braces the towers just fine which is why even the R doesn’t have a bar.

It also depends what bar and where it sits, but you should be totally fine to have both

edit: looked at your bar, it’s gonna make it a pain in the ass for sure. I’m like 99% sure you’ll have to remove it to install the can, but should be able to undo it for emptying with a little maneuvering without taking stuff apart
I will need to check it out a little closer, but getting the can in can't be worse than the brake brace haha.

As for the bar, it helped amazingly, highly suggest one. Plenty of performance parts don't come stock incl on the CTR :)
I removed the one on my Miata, which has a chassis design that apparently benefits greatly from the bar, and felt no difference. Then again, that car isn’t the stiffest chassis out there by far so maybe hard to tell.

good luck with the can! Well worth the effort

Interesting info that came up in my research. Pease report back if you get anything in your can. Also what your build is.
My build is stock and staying that way. I’m not expecting to find much in there, but for the cost of the can relative to the cost of needing walnut blasting and the other issues that may arise, I’ll run my can. There is too much variability between even the same engines for how much blow by they produce, based on maintenance history, weather, driving habits, etc. but generally speaking, DI engines are pre-disposed to some issues and I’d like to avoid them
I agree it's low cost high reward item. Thanks for the added info. I'm not going to be stock so more potential reward for running one.
i also binged a dozen videos from Engineering Explained and they also present a lot of great info on it:
Haven’t opened it yet. Going to when I do the oil change, that will be soon. I’ll post pictures of it and an update.
I'm having a really weird issue and hope you can chime in. So with the can installed I get this weird random rattle almost sounds like its coming from the dash and only hear it in the car. Checked under the hood and everything looked fine, I kept the can installed but removed the hoses and connected the stock PCV-Manifold line and the sound completely went away. Hooked the can back up, rattle is back.

Does yours make some weird noises? I'm wondering if the can is acting almost as a sound amplifier for noises in the crankcase at certain RPM]

edit: its not just me, https://www.civicx.com/forum/threads/mishimoto-catch-can-updates.5443/
I also have the rattle from my Mishimoto. It sounds like it's coming from the dash but I never had the rattle before I installed the can. I hope there is a solution for this as it is annoying.

This exact same thing is happening to me.
I called Mishimoto customer service and they told me to tighten then nut inside.
I hope this works.
It probably won’t, and honestly most of the time I can’t hear it listening to music. It’s just a pretty shitty product for $200, I bought it for their mounting bracket but the rest of the kit seems pretty trash for the price
Contacted Mishimoto about the can rattle. As expected they’re giving me the runaround “oh it’s the bracket” “oh it’s the factory plastic hose above the bracket”. Needless to say I do not recommend dealing with them and buying something else
Thanks for the info! Looking to do a catch can in the future so I will definitely keep this in mind when I shop around
They said "we don't have replacement filters but we can sell you a whole new can at a discount"...meanwhile, $1 https://www.aliexpress.us/item/2252...6!sea!US!752163139&curPageLogUid=DZmlApY1bvZ4
Ingredient Wood Plant Cuisine Seed

The fix, basically to keep the inner element from rattling
Rattle video:
See less See more
  • Haha
Reactions: 1
So a one dollar filter makes the catchcan....perfect now? Lmao
It’s more so the fact they are selling this thing for $200 and it has this flaw. And they don’t even have replacement filters and want to sell you a whole new can when the fix literally costs $1 to buy a new filter. The can WORKS fine but the rattle in the can ends up sounding like engine knock and people have spent big bucks tracking down noises that ended up being the fault of the can. My Miata has a different style can with a steel wool filter that doesn’t have this problem. Save $180 and buy this identical product. All I’m saying is Mishimoto is a ripoff and their service sucks

you can also just remove the existing filter and smash it down like I did to fix the rattle, but at that rate just buy the $20 can if you’re going to have to fix things yourself anyway
See less See more
  • Like
Reactions: 1
Have any closer pics/top down of where the hoses go? Something I need to look into and haven't yet to see where I need to make the connections for the inlet and outlet

View attachment 14204
I’ll post some for you later and give you hose measurements. Pretty simply though. The IN line comes from the back of the valve cover on the drivers side, the out line goes to the intake manifold on the drivers side.
Thank you :)
I know generally where the hookups go and I'm sure I can find some resources online, it'll be my first time messing with a catch can so just want to make sure I get it right!
I gotcha. Might be easier if I just make you a little video
Any chance you figured out the hose sizing?
Sorry dropped the ball on you there. I haven’t , but Mishimoto site says 3/8” I can try and measure this weekend if you still want. Been a bit busy
Nevermind! 2.0L is port injected, catch can not needed
If you can fit one for cheap, it’s still not a bad idea on any car, IMO. Port injected engines do run considerably cleaner, but they’re not immune from blowby. Yes the fuel cleans your valves, but if you’re moving oil and water (condensation) into the combustion chamber, it’s still going to make your plugs and performance not happy. Wouldn’t spend $200 on one, but it definitely won’t hurt anything to add one IMO.
  • Like
Reactions: 1
thanks for your input, have you ran one on a port injected car before? how did it run? also where would you connect the catch can in the picture I posted?
I run a baffled one on my built turbo Miata which is port injected. It runs just fine with a sealed can. It does catch stuff so obviously it’s doing its job even on a port car. Not sure I can help with connections on that engine with that pic, but I’m sure someone has a vid on YouTube, look up K20 catchcan
  • Like
Reactions: 1
1 - 20 of 62 Posts