Piston Slap: Earth Dreams of contaminated oil?

Hagerty Community Fan DavidHolzman writes:

At its last oil change, my best friend’s 2019 Accord’s 1.5L Earth Dreams engine had oil that was watery and smelled of gasoline. I will share the Blackstone oil analysis report with everyone (below).  The Accord has about 15,000 miles and he is concerned about the long-term durability of that engine. And if it’s a legit matter of concern, he wants to get a different car. What do you think?

Sajeev answers:

Fuel dilution is the act of incomplete fuel combustion, where unburnt fuel washes oil off the cylinder bores and eventually contaminates the oil in the crankcase. So yes, it’s a real concern. But don’t take my word for it, so let’s discuss the real question: how should one keep this problem at bay?

Honda is well aware of the 1.5-liter Earth Dreams’ problem, to the point that the automaker uploaded this video to its YouTube channel. Have a look and tell us how reassured you feel by it:

Honda disabled the comments, perhaps to ensure it does not have to deal with the blowby blowback on social media, but a class action lawsuit could bring relief for affected owners by this summer. What’s on the table is likely only for applicable CR-V and Civic owners, but that warranty extension and computer re-tune could be implemented for Accord owners who complain regularly enough to their dealers and Honda field reps. If so, it could take months or years to fully implement.

That might be too long for your friend, but that dreaded “over filled” oil dipstick isn’t the end of the world: just change the oil more frequently. It’s a modest time and money setback, and it beats dealing with the depreciation of trading in any vehicle, especially one in a less-popular sedan body style.

And thanks for sharing the Blackstone report, as the relative okay-ness (technical term) of their conclusions suggest that owner’s driving habits and oil change regiment is safe. I am far from a petrochemicals expert, but the odds of a catastrophic Earth Dreams engine failure under these conditions in the next 100,000 miles seems low. Hence why Honda is extending the warranty?

Blackstone thinks the oil was changed around 5400 miles, and suggests that 8000 mile intervals is acceptable. I would go with their recommendations, but perhaps someone with a strong background in automotive lubricants will chime in and say otherwise. And perhaps they’d also appreciate the same report on the owner’s previous 2014 Accord.

While the 2019 Accord has more than double the amount of fuel in the oil, what are the odds this negatively impacts engine health? Assuming consistent oil change schedules, I reckon any engine problem will happen well after the 100,000 mile mark, perhaps even past the 200,000 mile mark.

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