Subaru Forester Owners Forum banner

1 - 19 of 19 Posts

·
Registered
2016 Forester CVT
Joined
·
180 Posts
Discussion Starter #1
Here are pictures of my 2016 FXT valves at 46,000 miles (74,000 km). I ran Subaru’s top engine cleaner at 18,000 miles (29,000 km) and CRC GDI Valve Cleaner at 40,000 miles (64,000 km). Dual AOS catch cans were added at 33,000 miles (53,000 km). I was installing TGV/EGR deletes and figured that I might as well pull the entire intake manifold while I was at it and walnut blast the valves. Although not pristine, to my surprise these valves are not all that bad. I was about to start dragging out my blasting equipment but stopped when I realized that there was a learning opportunity at hand. Instead of blasting, I am going to use these pictures as a baseline and run CRC DIT Valve Cleaner at 50,000, 55,000, and 60,000 miles and see how they look afterwards. I’ll follow-up in a year or so.
 

Attachments

·
Registered
2013/14 2.5i-L CVT
Joined
·
798 Posts
I ran Subaru’s top engine cleaner at 18,000 miles (29,000 km)
Subaru AU recommend the Subaru Upper Cylinder Cleaner is used at 6,000 km/~4,000 miles, or at each service. It is a required service item here and included in the capped service price.

I can't say whether this makes a difference, but your result suggests it probably does. Except for those who don't drive many kilometre/miles, it would be cheaper than buying premium high octane fuels which are claimed to contain more detergents, etc.
 

·
Registered
2016 Forester CVT
Joined
·
180 Posts
Discussion Starter #3
Hey @slothman, thanks for the comment. I've heard Subaru Australia calls for the upper engine cleaner every oil change(ish) as you mention above. Not the case here in the USA for whatever reason. Perhaps Subaru of America wants to show operating and maintenance costs to be as low as possible.

Since the XT is Direct Injected, fuel never comes in contact with the intake valves so detergents don't help here. :-(
 

·
Super Moderator
2018 X3 M40i / 2016 X3 xDrive35i
Joined
·
1,622 Posts
Thanks for the post. I just did CRC intake valve cleaner at 12k and while it took a good 20 minutes or so it was very easy. Will keep it up every other oil change as preventative.
 

·
Super Moderator
2018 X3 M40i / 2016 X3 xDrive35i
Joined
·
1,622 Posts
I sprayed in the same location, map sensor. I took out the sensor, disconnected it (which throws a CEL) and then used metal ducting tape to create a rigid surface to block the opening, then pinholed it with a punch to stick the spray straw through. That kept it from dying. Then when done and everything buttoned back up and heat soaking for an hour, I just disconnected the negative battery terminal which reset the code. All is good.
 

·
Registered
2018 Forester 2.5I Prem CVT
Joined
·
25 Posts
Try doing before and after pics when using the spray cleaners. You'll likely find no difference. Spray cleaners tend to work well on soft deposits which valve deposits are not soft.

Catch cans will also likely not make any difference.
 

·
Registered
2016 Forester CVT
Joined
·
180 Posts
Discussion Starter #8
@badtlc, a lot of people share your skepticism of the spray cleaners. Removing and reassembling the intake components is too much of a time-consuming PITA to inspect results after each treatment, hence my intention to revisit at 60K miles. I think the results will be interesting regardless of the outcome.

The effectiveness of oil catch cans are thoroughly debated in this forum and other places on the internet. I’ll avoid reengaging it here.
 

·
Registered
2013/14 2.5i-L CVT
Joined
·
798 Posts
Hey @slothmanPerhaps Subaru of America wants to show operating and maintenance costs to be as low as possible.
I wish Subaru AU had the same philosophy. It has set capped service prices, an upper limit which dealers can charge during the warranty period, and they aren't cheap, ranging from AU$350-760, about US$250-550 which is outrageous given Toyota dealers generally charge about half for the equivalent service on RAV4s. At least the 2019 models now only require annual servicing.


I live in a small rural town so only use the car to tow my boat, or the occasional trip into the city and therefore do fewer miles than most. Maintenance is my biggest expense, considerably more than I spent on fuel. The engine intake must be so clean you could eat off its internals!
 

·
Registered
2018 Forester 2.5I Prem CVT
Joined
·
25 Posts
@badtlc, a lot of people share your skepticism of the spray cleaners. Removing and reassembling the intake components is too much of a time-consuming PITA to inspect results after each treatment, hence my intention to revisit at 60K miles. I think the results will be interesting regardless of the outcome.

The effectiveness of oil catch cans are thoroughly debated in this forum and other places on the internet. I’ll avoid reengaging it here.

I only suggested doing a before/after of spray cleaners because it has been done at other places on the net and the results were no change in hard deposits.

You can burn off deposits, though, without the use of any chemicals. Much cheaper and shown to work well on other cars.
 

·
Registered
Joined
·
29 Posts
Here are pictures of my 2016 FXT valves at 46,000 miles (74,000 km). I ran Subaru’s top engine cleaner at 18,000 miles (29,000 km) and CRC GDI Valve Cleaner at 40,000 miles (64,000 km). Dual AOS catch cans were added at 33,000 miles (53,000 km). I was installing TGV/EGR deletes and figured that I might as well pull the entire intake manifold while I was at it and walnut blast the valves. Although not pristine, to my surprise these valves are not all that bad. I was about to start dragging out my blasting equipment but stopped when I realized that there was a learning opportunity at hand. Instead of blasting, I am going to use these pictures as a baseline and run CRC DIT Valve Cleaner at 50,000, 55,000, and 60,000 miles and see how they look afterwards. I’ll follow-up in a year or so.
You cant tell anything by that photo, the only thing that matters is the valve seat and valve face
 

·
Registered
'04 GTI 1.8t Manual
Joined
·
70 Posts
Hey @slothman, thanks for the comment. I've heard Subaru Australia calls for the upper engine cleaner every oil change(ish) as you mention above. Not the case here in the USA for whatever reason. Perhaps Subaru of America wants to show operating and maintenance costs to be as low as possible.

Since the XT is Direct Injected, fuel never comes in contact with the intake valves so detergents don't help here. :-(

question...

who is more correct? SoA or SoA :| ....I mean Subaru of America or Subaru of Australia?

It is interesting to see the different maintenance practices/recommendations on the same vehicle, the same engine, roughly the same oils/parts, but different gasolines/fuels.

Does it have to do with the country's environmental laws/factors? Is it more of allowances by the government to allow manufacturers to commit to these practices?

Has it always been a part of the car culture in Australia to offer these capped service contracts? or is it a recent trend, within the last 5 or even 10 years?
 

·
Registered
2016 XT
Joined
·
255 Posts
As far as I know Subaru OZ has recommended the upper engine cleaner for a long time even on non DI motors. I suspect its related to fuel quality/ carbon buildup in general or its just another excuse to charge you more.

Capped price servicing came in around the last ten years or so with other brands, Subaru started in the last 4 or 5 years iicrc, due to other brands bringing it in as a selling point. but not all the Subaru dealers offer this. Either way the Subaru CPS is way too expensive for what you get for your money (probably the most expensive out of the other Japanese brands and others..) its better than having to pay for it without the capped price. but when they charge you $100 for the same oil you can buy from the car stores for around $60 not on discount.. it says it all really.
 

·
Registered
2015 Forester XT Touring
Joined
·
653 Posts
Here are pictures of my 2016 FXT valves at 46,000 miles (74,000 km). I ran Subaru’s top engine cleaner at 18,000 miles (29,000 km) and CRC GDI Valve Cleaner at 40,000 miles (64,000 km). Dual AOS catch cans were added at 33,000 miles (53,000 km). I was installing TGV/EGR deletes and figured that I might as well pull the entire intake manifold while I was at it and walnut blast the valves. Although not pristine, to my surprise these valves are not all that bad. I was about to start dragging out my blasting equipment but stopped when I realized that there was a learning opportunity at hand. Instead of blasting, I am going to use these pictures as a baseline and run CRC DIT Valve Cleaner at 50,000, 55,000, and 60,000 miles and see how they look afterwards. I’ll follow-up in a year or so.
I did none of this and when I had mine walnut cleaned at around 35k miles my valves looked pretty good. I like to think it's down to clean living and quality 93 octane Texas fuel :)
 

·
Registered
2017 Forester XT
Joined
·
184 Posts
@aggie113 Maybe due to other factors such as regular engine oil changes and driving pattern. I presume you change your engine oil regularly and seldom do short trips.

Removal of the EGR system will help too. Did you remove yours?
 

·
Registered
2015 Forester XT Touring
Joined
·
653 Posts
@aggie113 Maybe due to other factors such as regular engine oil changes and driving pattern. I presume you change your engine oil regularly and seldom do short trips.

Removal of the EGR system will help too. Did you remove yours?
Emissions systems is fully stock. Only thing I've added is an AP stage 1 map, though it's been off more than it's been on the car. I frequently do short trips as my work is less than 15 minutes away. Oil is changed every 5k miles and sent for analysis, nothing special :)
 

·
Registered
2016 Forester CVT
Joined
·
180 Posts
Discussion Starter #17 (Edited)
I’m back with the 60,000 mile (96,500km) gunky valve report as promised. Do the spray intake cleaners work? I’m thinking NO, not really. The latest pictures show zero improvement. As a reminder, I installed oil catch cans and deleted the EGR so there should minimal contaminates going through the intake. The only source of contamination is from the turbo, where some oil is still getting by, but not a lot. I only used the Subaru Top Engine Cleaner, not the CRC DIT valve cleaner, at 50,000 and 55,000 miles. Did not apply treatment at 60,000 before removing the manifold and taking these pictures.


Please consider that my experience is only one data-point and not scientific evidence of the spray valve cleaners’ effectiveness. Individual results may vary + my experiment is far from perfect.


As for me, I’m not going to use the valve cleaner again (or walnut blast) until my engine becomes symptomatic of excessive contamination. My personal experience is suggesting the spray cleans don’t make a net difference.
 

Attachments

·
Super Moderator
2018 X3 M40i / 2016 X3 xDrive35i
Joined
·
1,622 Posts
I wouldn't go beyond what you're doing. It looks very clean....very little physical buildup on the valves I'm seeing...nothing that would rob power...and it certainly doesn't look like enough that you'd be building up and causing poor seating of the valves against the head casting.

As a side note, how are you getting these pictures? USB scope? I should do the same for mine with nothing aside from CRC cleaning...then I could do a before and after treatment. edit: nvm missed that you removed the manifold.
 

·
Premium Member
2019 Crosstrek 2018 XT
Joined
·
14,213 Posts
Thanks. I have independently come to the same conclusion bu reading up on the problem.
My solution to the problem is to trade it in in 5 or 6 years. By that time my extended warranty will have run out. Thanks!!!!
 
1 - 19 of 19 Posts
Top