These UOAs were done in succession in response to a strong fuel smell I noticed when checking the oil in my 2015 CRV (DI, normally-aspirated). I was hoping the fuel smell was of no consequence, but as you can see, I was wrong and have entered Polaris Labs "panic" zone for fuel dilution. As you may note, the fuel dilution values are based on tests using gas chromotography ("GC"), which is supposedly the best method available to we civilians.
These samples were all drawn immediately after 100-400 mile Interstate runs in mild weather, so short-tripping isn't an answer. And Honda's Maintenance Minder (which is supposedly "Intelligent) points toward a 10-12,000 mile OCI.
I took these results to my dealer who, after consulting Honda's Tech department, ran a series of tests and found nothing wrong. My dealer was very supportive, but had no other options available. I asked American Honda for help, forwarding these UOAs and explanations to them. American Honda declined to do more investigation unless I had a driveability issue or CEL, and wouldn't say if this was a normal characteristic of the engine or not.
So I'm left trying to figure out what this means. Despite the fuel level, wear metal numbers seem good, especially for a relatively new engine, so maybe none of this matters. UOA 3, which shows a lower level of dilution was taken after 1,100 miles on a fresh change using only 93 octane fuel, so this could be an engine that behaves like Mazda Sky-Activs and benefits from premium, or it could be low simply because it takes time for fuel to accumulate. I'll test this more fully.
What do you folks think:
1) Bad car, bad engine, on the road to ruin, dump it or don't keep it past the warranty period?
2) Proceed with caution, using something like a 4 month/4k OCI and see what happens? The oil's viscosity is slipping below grade by that point.
3) Behave like a typical Honda owner, rely on the Maintenance Minder, drive it and be happy?
I don't know that oil brand makes much of a difference here and will stick with 0w-20, at least through the warranty period. A bad PCV valve could be an issue I suppose, but that seems pretty unlikely.
I'd appreciate any thoughts or suggestions. Thanks!
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