Anglomoil GT40 5W40 3.6k miles Legacy GTB 109k tot

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Hi, as seen in the following I have had high silicon as well as fuel dilution. After the first oil analysis I changed from a K&N mesh style filter to a paper filter and this has not had any affect on my silicon levels. I have no idea if it can have any effect but I have a silicon inlet and inter-cooler piping. My PCV set-up is stock so I have got a small amount of oil going through the system, not sure if this can pick up any silicon. I have not recently used any silicon sealant on the engine either.
Also after the first analysis, I cleaned my MAF and ran injector cleaner in the car. I have also noticed a lot fuel correction in the low airflow (around idle) area of my car, around 9-11% fuel is being reduced in this area. This makes me think that I might have an injector that is not sealing correctly and my car is pulling fuel in closed loop fueling to obtain a stoichiometric ratio, which will actually be 3 lean and still one rich cylinder. Could this be my source of high fuel dilution? For the second analysis I had been doing some longer drives (30-40 minutes)regularly so I do not think the issue is simply due to short trips.

Any input on either issue or anything else with the UOA would be much appreciated. Bellow are the results as well as a learning view from my car.









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VIRGIN OIL DATA

ANGLOMOIL RASYN GT40 5W40
VISC@ 100C 14
VISC@ 40C 82
TBN 11.4

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CAR INFORMATION

MAKE SUBARU
MODEL LIBERTY/LEGACY GTB
YEAR 2007
ENGINE EJ255
MILES 109K

Regards,


Liam
 
That is a rather unique name for oil. Sorry, I can't answer your question. But, OEM is usually great for air filters.


Respectfully,


Pajero!
 
Doesn't look too bad. Are you sure silicon isn't simply an additive of this oil?
As for fuel dilution, it doesn't seem to affect the wear valies too much. Did you sample the oil cold?

Could you have a small vacuum leak somewhere, or at an injector? Is idle rough ? What do the spark plugs look like?
(Is this a returnless injection system ? How's the fuel pressure regulator doing ?)
 
Thanks Pajero,
It is an Australian brand of oil so I assume most people will not have heard of it.

Popsy, I am not sure, maybe the silicon is an additive. I have two friends who use the same oil who are about to do an analysis so it will be interesting to see if they get the same results. I could also do a vigin oil sample to find this out, the TDS does not specify the additives used.
The oil was sampled while hot both times. I do not suspect a vacuum leak as any post maf vacuum leak would result in fuel being added as opposed to removed. I am suspecting that the issue is a leaky injector. It is not a returnless fuel system and I have not monitored my fuel pressure/regulation, maybe this is something I should look into. Generally the car drives great, there can sometimes be the slightest rough idle that is hardly noticeable, nothing like a bad misfire or running on 3 cylinders. I have not checked the sparkplugs for any indication of a misfire, I think it would be too minor to notice and also it is a boxer engine with coil of plug, so pretty annoying to pull the plugs.

Regards,

Liam.
 
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