Additional Maintenance Items for Subaru FB engines

Subaru FB engines (FB20, FB25, FB16) require additional care outside of the typical engine air filter and oil changes.
Periodically cleaning the MAF sensor , Throttle body , and PCV valve will ensure that your Subaru FB engine stays strong and reliable.
IG: @canigetthatextracrispy
Impreza Tuning: 4roller.github.io/subaru-impr...

[@laserward]

Always love seeing an upload from Jason. Favorite channel these days. Hope we get to see more of you tearing up the roads soon

[@JasonLeung-4roller]

Thanks for the nice words. I hope to get back into doing some driving videos soon.

[@DaDaDo661]

Thanks, i wanted to completely remove the throttle body off of my Outback (2020) but saw there were coolant hoses running through it. I just left it on and did the blind spray and wipe.

[@b374mxg]

I change my oil and filter every 3,000 miles with the Subaru 0W-20 oil and their oil filter. Does not use one drop. 2021 Legacy 2.5 non turbo engine.

[@JasonLeung-4roller]

With normal use (regular driving) I can see these engines not having much blow by. High rpms tend to push more oil.

[@salehesenga5406]

this is good so much better

[@JasonLeung-4roller]

Better than what? Thanks!

[@robb7733]

Outstanding video! Where can I buy that air intake hose? I'm hitting 50k on my 18 Forester and I picked up a new PCV value at the dealer for $25. I felt better about doing that instead of cleaning the old one. $25 isn't bad.

[@JasonLeung-4roller]

Hey thanks mate! Here is a rundown of the intake I put together. kzbin.info/www/bejne/jKq1oYR4mp5qmbssi=tzAF1H0zMZ5fYyoO

[@robb7733]

Thanks! @@JasonLeung-4roller

[@Mike_44]

I saw a video of this famous Nissan Skyline engine builder from Japan, where he recommends changing the engine oil on all cars, every 2K-3K miles to really make sure engines last and perform at their best. He mentioned at 5K miles is way too long and by then, the oil has been broken down so much it doesn't really protect against friction as well.

[@JasonLeung-4roller]

A GTR engine is a sports car engine with high horsepower and turbo. In most cases that car is used for racing. So the demand on the engine is much higher in a shorter time period. A racing engine should have its fluids checked and changed much more often than a regular grocery getter. For these small low horsepower FB engines... It does not need oil changes as often. Though it does not hurt. If you bang on the throttle with this little engine, then by all means 2000-3000 miles for an oil change is good preventative maintenance.

[@Mike_44]

@@JasonLeung-4roller Makes sense. 👍🏻

[@Motorsportsgeek]

naturally aspirated maintenance is reasonable, the turbo charged maintenance consists of engine replacements lol

[@JasonLeung-4roller]

It would seem that way. NA especially these port injected machines are great reliable workhorses. Turbos... have their place. But it ultimately comes down to higher maintenance and seeking reliability

[@emeryguo5158]

I'm considering adding camber plate to my stock strut on my 20 legacy, any recommendation?

[@JasonLeung-4roller]

The OEM front strut does have camber adjustments via an eccentric bolt near the knuckle. The adjustability however is only 0.5-1 degree. Camber plates on stock struts I have not seen. You would typically want a coilover with a spherical bearing at the top to handle a camber. The other option would be to get some sort of aftermarket top hat. As far as adjustable top hats I know not.

[@civilengineer2024]

Spraying throttle body cleaner into the throttle body without removing it is fairly useless. Oh, and you would be surprised at how bad they can get without any sort of idle problems. One of the biggest symptom i see is bad gas mileage.

[@JasonLeung-4roller]

I would disagree. For an engine which has never been cleaned, then a deep cleaning like taking off the TB would be recommended. However with regular maintenance, spraying just the hinge pivots occasionally, will very much reduce the likelihood of the throttle body gumming up completely. I have only 50k on my car but when I look at my throttle body, it's clean. It's because I run a catch can as well as do the regular maintenance spraying. Good luck with your car!

[@civilengineer2024]

@@JasonLeung-4roller do what you want on your own car, but i have a combined 400,000 miles on 3 fb foresters. The TB looks fine from the upstream but in actuality is really dirty around the margins if you pull it.

[@JasonLeung-4roller]

@@civilengineer2024 do all of your cars have the stock intake? Do any of your cars have catch cans on the breather port? Do any of your cars have air oil Separators? The latter two go a long way to reducing oil vapors entering the intake tract. Subaru OEM at least for the FB engines, dump a bunch of oil through the PCV and breather, especially if you use the engine at high RPMs. I noticed the OEM air intake tube baffles full of oil. Then my throttle body was gummed up causing codes. I added a catch can to intercept the oil vapors. So in my setup I only need to spray occasionally to help keep it working smoothly. I have no doubt that the backside of the TB will have oil build up. Have you ever taken off your intake runners? Around the tgv valves, they are covered! My point is that it doesn't have to be super clean, only clean enough for the hinges to turn freely. Preventive maintenance is all I am trying to convey. The risk for most people pulling throttle bodies and cleaning them is bent butterfly valves. Or broken servos. If you are mechanically inclined, by all means. Take it off and clean it. Happy motoring !

[@civilengineer2024]

Your video is titled for a normal FB engine maintenance. I think you’re being misleading if you need to provide this much backstory explanation. Yes, you have to be careful when you pull the TB, but that doesn’t change the fact that you likely have to pull it in order to properly clean it.

[@JasonLeung-4roller]

@@civilengineer2024 apologies for being misleading. I still stick to my original video recommendations. To keep a stock engine working well, you only need to spray the throttle body down every other oil change. Anything beyond that is typically outside of the comfort level of a normal user. You can take it to a mechanic or dealer to diagnose what issues you may have. Enjoy your Subaru.

[@Nightowl82]

Have you ever thought of painting the aluminum intake pipe black?

[@JasonLeung-4roller]

I have thought about covering or wrapping the pipe in some sort of insulation material, be that rubber or silicone. That is to keep the intake charge insulated from the engine bay. Black colours do provide good emissivity so I hear that.