Last oil change back in October, I put M1 ESP 5W30 in. I underfilled slightly (3.5 vs 3.7qt) to make it easier to track a rising oil level on the dipstick. I then turned off ECON mode and started using 91 octane exclusively. So far, through the winter and into spring (6 months and 2600 miles of mostly short-tripping) the oil has not moved up on the dipstick at all. Not sure how much to attribute to ECON being off and how much to attribute to the higher octane fuel, but one or both of those seem to be doing the trick. Last spring, using 87 octane and leaving ECON on all the time, I could easily see rising oil levels on the dipstick despite warm weather and a ~2000 mile road trip. Honestly, I figured 2000 highway miles in less than 2 weeks was the perfect scenario for no fuel dilution, yet I saw the oil level climb on the dipstick significantly during that trip. Anyone else have success stories with combating fuel dilution? What did you do?
Think I may have solved fuel dilution problem in our '18 CRV
- Thread starter himemsys
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I have only one Honda data point. I rented a 1.5t Accord last year and drove it for 2 weeks. Multiple long highway trips, between Jupiter, FL and Sav, GA (400 miles each way) along with weekly around town use.
I used premium 93 for one tank, and sadly did not record the oil level before and after the tank. However, the oil was up 1 quart over the 2500 miles I drove the car.
Of note, the 93 octane fuel did result in 2mpg worse highway MPG. And ethanol free fuel made only a modest improvement over our 87 octane, up to 10%E, fuel. The vast majority of modern vehicles really respond with a large MPG improvement with zero E fuel.
I used premium 93 for one tank, and sadly did not record the oil level before and after the tank. However, the oil was up 1 quart over the 2500 miles I drove the car.
Of note, the 93 octane fuel did result in 2mpg worse highway MPG. And ethanol free fuel made only a modest improvement over our 87 octane, up to 10%E, fuel. The vast majority of modern vehicles really respond with a large MPG improvement with zero E fuel.
A whole quart more after just 2500 miles. What a piece of junk engine.
Are you saying you checked the oil level when you first got the car and again after 2500 miles?
+1
I've noticed the same on my 1.5 Honda as well. But I don't have an "ECON" mode.
Regardless, over the past 2 years I've been running 91 octane exclusively and haven't noticed the oil level go up at all.
Good luck trying to convince a Honda owner they need to run high octane fuel to fix the fuel dilution issue.
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Bought a new Civic Coupe Turing 2016, 80k on now, son owns last 4yrs. We just monitor in the cold weather til it's up a half qt. then siphon off a full qt. and replace that with 1/2qt. fresh 0/40 Edge..repeat couple times per winter...ez peazy.
4WD
$50 site donor 2024
Couple things
1. Just how representative of Honda do folks see this post
2. GM or Kia the howler monkeys would violently erupt here
1. Just how representative of Honda do folks see this post
2. GM or Kia the howler monkeys would violently erupt here
I'm surprised that 91 vs 87 octane would make that much difference in fuel dilution. More advanced timing with 91 octane allowing a more complete fuel burn?
It's pretty indicative of Honda's shady practices if you look at how they slowly cheap out YoY on a single model. Slowly they remove bits and pieces to shave every last penny while also raising the price because "inflation". Go try a new 2023 accord and take a very close look at everything, at first glance it's nice, on closer inspection, to get a car that's built with good attention to detail you're being upsold to a 39,500 touring trim. Just go compare the trims on their website, want more than 4 speakers? Jump like 3 trim levels.
Same with engines. The 2.0 isn't as bad because it's just a derivative of the legendary K series but the L15 is textbook cheap in every sense of the word, and you still need to pay well over 30k for a civic to not get the base motor (which is arguably more reliable).
It's just nice that most Honda (and Toyota) owners also are some of the most meticulous car owners, servicing exactly per the manual or dealership recommendations which is usually overkill.
Then look at how Honda addressed the L15 fuel dilution....a software update that dumps even more fuel into the engine at cold start and run at higher idle to warm up faster, which doesn't help with short trips anyways because it's been proven that the L15 runs pretty cool and at 0°C takes 30 minutes to warm the oil up to a temperature where the fuel will evaporate.
I think it was Hondata that noticed that the most optimal timing in Honda's is actually at 100 octane...which is bizarre.
I think the theory is Honda TGDI engines respond to pre-ignition by enriching the mixture first, then retarding timing. If that’s the case, 87 octane could make the issue worse. But who knows? There are millions of these things out there running 87 with few reports of failure or short life span. Unlike some others…
Depends what you consider a failure.
The L15 is very prone to failing because of other issues not related to oiling, ex: head gasket failure (which is actually quite common around the 100k mile mark).
You're actually correct about the timing. This can be observed when aftermarket tuning these TGDI's (like my personal accord).
My presumption is that a head gasket issue is pretty easily corrected by the OEM. So the 100k failures (if that’s the case) would be early model years. And in typical Honda fashion, no extended warranty or announced goodwill program.
Now you know why the auto makers want a new high octane standard.
ethanolproducer.com
House bill aims to create high-octane, low-carbon fuel standard | Ethanol Producer Magazine
Rep. Mariannette Miller-Meeks, R-Iowa, and 19 cosponsors on March 30 reintroduced the Next Generation Fuels Act, which aims to establish a high-octane, fue
Yes, I was interested to see if the oil level would increase.
They want that for efficiency. A higher compression ratio is more efficient in extracting the energy from the fuel.Now you know why the auto makers want a new high octane standard.
House bill aims to create high-octane, low-carbon fuel standard | Ethanol Producer Magazine
Rep. Mariannette Miller-Meeks, R-Iowa, and 19 cosponsors on March 30 reintroduced the Next Generation Fuels Act, which aims to establish a high-octane, fue
