Long Term 5w-30 use in Honda 1.5t

So far so good, MPG still seems to be about the same. We did get warmer weather this week and MPG is better due to not running the heater.

Any sense changing the oil more frequently than 5k?
Heater has zero effect on MPG….it is just hot water that didn’t go to the radiator….

You got better mileage because you didn’t have as cold of a start and as long of a “warm” up when the OAT is warmer.
 
Heater has zero effect on MPG….it is just hot water that didn’t go to the radiator….

You got better mileage because you didn’t have as cold of a start and as long of a “warm” up when the OAT is warmer.
if anything it would probably be slightly more efficient with heat running, but not significant enough to notice.
 
Heater has zero effect on MPG….it is just hot water that didn’t go to the radiator….

You got better mileage because you didn’t have as cold of a start and as long of a “warm” up when the OAT is warmer.
Heater pulls heat from the very efficient engine which already is known to take a long time to get to operating temp. This makes the warmup cycle longer even while gently driving, and also causes the idle stop start not to work since the engine has to stay running to keep the heater on. Both of those hurt fuel economy outside of the general guise of winter blend fuel, cold air density, and windier conditions of the season.
 
Heater pulls heat from the very efficient engine which already is known to take a long time to get to operating temp. This makes the warmup cycle longer even while gently driving, and also causes the idle stop start not to work since the engine has to stay running to keep the heater on. Both of those hurt fuel economy outside of the general guise of winter blend fuel, cold air density, and windier conditions of the season.

yes, until the engine and vabin get up to temp, then there's very little difference anymore. but before that the difference is significant.
 
yes, until the engine and vabin get up to temp, then there's very little difference anymore. but before that the difference is significant.
Apparently people with these L15 turbo engines who monitored their water temps in the cold actually saw them dropping at idle to the point of the little water temp indicator bars dropping from 4 to 3, I don’t know what that is in actual temperatures though. I can tell you that when it gets to around freezing, even with the heater and stuff off at a light the car does not sit as long with the engine off before idle stop start kicks it on again, as compared to even when it’s in the 50s or 60s when I can literally sit at a light for minutes at a time without the engine off. One of the triggers for idle stop start disabling itself is if engine temperature falls below a certain threshold. I don’t think the car is going into warmup enrichment every time but it’s really amazing just how fast everything cools down in the cold
 
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seen it on my own car, the engine had just reached normal operating temp when I reached stop 'n go traffic, the temperature dropped back down, more so with s/s engaging.

got stuck behind a farm tractor a few weeks back and doind 25-ish mh vs the normal 45, the engine need twice the distance to get to temp.
 
The more I read these posts about the issues with the 1.5T in Hondas, the more I’m glad to have the 2.0 engine in my Civic. No problems with long warmup times, fuel dilution, having to do early oil changes. This engine just keeps plugging away reliably and getting incredibly good fuel efficiency and it really isn’t that much slower than the 1.5T either. I bet in normal part throttle driving it probably feels slightly more powerful too.
 
The more I read these posts about the issues with the 1.5T in Hondas, the more I’m glad to have the 2.0 engine in my Civic. No problems with long warmup times, fuel dilution, having to do early oil changes. This engine just keeps plugging away reliably and getting incredibly good fuel efficiency and it really isn’t that much slower than the 1.5T either. I bet in normal part throttle driving it probably feels slightly more powerful too.
No it doesn’t feel more powerful

The 1.5T is an amazing little engine

This warm up time thing is a red herring and fuel dilution happens but does it really impact durability?
 
Yea I don’t think there’s really any issues to write about for most people looking to get to even 200k miles. Sure the k20 will probably have less issues getting there but there’s no real widespread problems here, even the fuel dilution was only an issue for a very minor minority of owners. But we are car guys so can’t leave anything alone even if it’s sometimes for worse.

Also having driven the 2.0 and 1.5, no comparison the 1.5 feels amazing in comparison, I barely ever go past 2000rpm because of the abundance of torque combined with the CVT hearing. 2.0 is more rattly and you definitely have to rev it higher to get the same level of acceleration.
 
I'm another big fan of the 1.5T, from the standpoint of the driveability, and enjoyment of use. It's amazing to me how much low and mid range torque the engine puts out. I've thought of putting a "tune" on mine, but honestly, I'm happy with how much power it already has.

Regarding fuel dilution, it's true, but not enough to hurt the engine, in most use cases anyway. And we are all about oil here, and oil changes are FUN! Just change the oil at 5k, or 6 months (for short trippers). What's the problem?
 
I'm another big fan of the 1.5T, from the standpoint of the driveability, and enjoyment of use. It's amazing to me how much low and mid range torque the engine puts out. I've thought of putting a "tune" on mine, but honestly, I'm happy with how much power it already has.

Regarding fuel dilution, it's true, but not enough to hurt the engine, in most use cases anyway. And we are all about oil here, and oil changes are FUN! Just change the oil at 5k, or 6 months (for short trippers). What's the problem?
How do you know this? There are several ways that fuel dilution is detrimental, how are you determining an engine isn't being hurt?
 
How do you know this? There are several ways that fuel dilution is detrimental, how are you determining an engine isn't being hurt?

Oil analysis reports are generally favorable. The engines don't burn oil. I've been hanging out at CivicX since 2017, and I've never seen a report of engine damage caused by oil film failure.
 
So you contend that cheap and "generally favorable" spectrographic analyses prove that fuel isn't hurting the engine.
True that.

But as much Honda hate as there is, if the 1.5T engines were completely failing - by volume out there alone - it would be in the news.

Sure they are not perfect - Honda - frigging niggly crap. And I hate fuel dilution more that the next fat person, fuel is not killing the engines super quickly. Also, maybe someone can whip out MTTR or M$TR for the 1.5T starting from day one. Maybe a top 5 causes of death as well.
 
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