Nissan MR20DD fuel dilution in oil

Joined
Jun 12, 2010
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500
Location
virginia
I've been doing nearly every one of the oil changes on our 2017 Nissan Rogue Sport. I never realized just how much fuel could be in the used oil. (This engine turns the oil black in a very short time as well.) I installed a Fumoto valve about 3 months ago when I did an oil/filter change. I was curious just how fast it would drain oil, so I decided to take 2 Qt's out just recently. I'm so very glad....the oil had a very distinctive gas smell. This is going to change how often I change the oil. Thankfully after the 2nd O/C of using 0w-20 oil, I decided to use a very light 5w-30 grade of oil. (Pennzoil Ultra Platinum.) The engine runs superb! Just hope won't have to deal w/other issues related to DI engines. (Carbon build-up on valves etc...) Plan on keeping car for a very long time. Just my observation and advice on not using a 0w-20 grade of oil in this engine. Would using a larger oil filter (same by-pass pressure) help in any way? (I have a few Mobil M1-110's and Fram XG-7317's ready to use in the near future.) Thanks for all...
 
Filter won't filter out gas. I'd be at the Nissan dealership asking why my oil smells like gas and telling them to fix it.

Gas is supposed to be burning, not leaching into the crank.
 
The percentage of fuel in the oil is unknown. From my understanding, all DI engines have this issue to some extent. I'll just be changing the oil more often and really keep an eye on it. (This is the first time I was made aware of this because on all my previous oil changes I drained the used oil directly into an oil drain pan under the car which I never really inspected.) It's also just a little disconcerting just how black the oil gets in so few miles.
 
Smell and color are meaningless.

Get UOA with fuel dilution, and not from the drive-thru lab commonly used. Post the results.

Not all DI engines have this issue. Not all driving styles have this issue.

Unless the manufacturer has some magic method of cleaning the intake port/valves, then IVD is inevitable. This just means 1 more maintenance step is needed, and should be considered as prevention or preventative maintenance. Practice foam/spray/liquid IVD cleaning in some time or mileage based interval. All my GDI cars get this yearly.

The oil change interval, from the owners manual, is 5000 miles or 6 months, whichever comes 1st. Seems to be pretty safe, especially when using a synthetic oil, synthetic filter, larger filter, and a single or more viscosity grade increase(weather permitting).

Did you test the Fumoto valve for your application? Drain oil completely with Fumoto valve, and then remove to see if there is any oil left behind, and measure amount left behind.

Don't be paranoid. Get the UOA and see if there is a problem.
 
Never thought of IVD preventative maintaince. Thank-you for mentioning. Could you please elaborate....which method do you use? Yes, a proper test would be prudent. Presently I do twice yearly OC's regardless of miles. (Start of winter/summer.) 5k miles per year w/somewhat of a short drive to work. (around 10 mi.) I know many would say I'm wasting superb oil....but we really want the car to last and last and by nature I really believe in overly maintaining. And since joining this site, I have quite a bit of oil! As far as the Fumoto valve, I'd bet there's very little oil remaining in the sump after a complete drain. (I just did a 2 qt. drain.) BTW, with the valve model I installed the first two qt's came out under 3 minutes! Fantastic. I not overly concerned. The 5w-30 viscosity helps IMO. Thanks again.
 
I use a bottle fed or spray can IV cleaner every year. Just follow the directions on the can.
I've used:
Royal Purple Max-Blast(possibly discontinued but NAPA has it)
https://www.berrymanproducts.com/products/maintenance/berryman-intake-valve-combustion-cleaner/ (this replaced the metered HEST)

No brand loyalty here so I recommend alternating among the brands available.

Like RoyalPurple, the Lubegard 9000 has been discontinued.

And, it usually will take a 2nd person to maintain engine rpm as some products will cause engine to stall.

I do recommend a quality PEA/PIBA/equivalent for the tank prior to performing the IVD cleaning. Basically, I want the pistons/combustionchambers/injectors to be as clean as possible. And, since solvents are the nemesis to octane, I recommend to then fill the vehicle up with premium fuel to reduce detonation during/after the usage of the above products. After you performed the cleaning, soaking, and a gentle ~20 minute drive to clear out the product, I'd then recommend an oil/filter change.

If you are not a do it yourselfer, then find a shop for :

IV/port cleaning is nothing new. Have used products since the 1980's(usually to make a vehicle pass emissions), especially after the quality degradation of EPA fuel in ~1992ish, and the reason why toptier and those PEA FI products was developed and marketed.
 
Without a UOA you really don't know if you have a worrysome amout of fuel in the oil. A very small amount of fuel in 5 quarts of oil will smell strong of fuel. Ed
 
You are absolutely right. This (MR20DD) is the first gas direct engine we've ever owned. I'm saving a sample amount of used oil. Will drain another couple of qts in a 2-3 months and see how it compares. Not overly concerned just unaware of this engine could have this issue. Will use the CRC IVD cleaner mentioned above @ the next early winter OC. (That's again for that info!) I'm very glad I started using a higher viscosity of oil after the the first year. No worries...Bill.
 
Are you draining your oil after making long trips? I think I sent oil analysis once after starting engine & allowing it to idle for 15 minutes, so I could do a hot oil change. I think I was getting a misrepresentative sample. I have now been making sure that I only drain oil after I have driven the vehicle for at least 30 minutes to an hour of highway driving. Making sure that the vehicle has reached operating temperature for an extended length of time.
 
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