My Civic doesn’t convert to miles accurately

Patman

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Guelph, Ontario
I know it’s being really picky but my 2016 Civic doesn’t convert into miles as accurately as I feel it should. Yesterday when I did my oil change the odometer was reading 261,711 km and when I switched the display over to miles it converted to 162,553 miles. But if you do a proper calculation into miles (multiply by 0.6213712) the actual miles is 162,619. I haven’t double checked the Corvette to see if it’s any more accurate than this.

What kind of accuracy are you guys seeing with your vehicles?
 
I would say that's because they don't measure miles or km, they count wheel revolutions. so either or both the number of revolutions per km or mile are off. But it seems be within 0.1% of each other, how much more accuracy of an inaccurate nuber do you need? they don't account for tyre wear or low tyre pressures etc....

Haven't ever put mine in miles.
 
I know that I’m definitely nit picking and that in reality neither of the values are 100% accurate because of tire wear. But I still would have figured that the two values would be tracked at the same rate so then the conversion should theoretically be more accurate than it is.
 
I know that I’m definitely nit picking and that in reality neither of the values are 100% accurate because of tire wear. But I still would have figured that the two values would be tracked at the same rate so then the conversion should theoretically be more accurate than it is.

What we don't know is whether it's the miles that are technically incorrect, the kms that are incorrect, or both :D
 
better change your tires every 1000 miles then.. the odo might be off more from worn tires :)

Generally Odometers can be off significantly.. sometimes there is a correction factor from the mph displayed as well.
 
Traditionally, as a favour to the driver, the indicated speed is usually 2% higher than actual to keep the police on the side of the road. As to the miles /kilometres accumulation, I've never been bothered to check.
 
Traditionally, as a favour to the driver, the indicated speed is usually 2% higher than actual to keep the police on the side of the road. As to the miles /kilometres accumulation, I've never been bothered to check.
With my ex wife’s BMW the speedometer was off by 10% (it would read faster than actual, according to all of the road side radar readings) but the odometer wasn’t off by 10%. So the two didn’t tie in together in that car (2010 328i)
 
Traditionally, as a favour to the driver, the indicated speed is usually 2% higher than actual to keep the police on the side of the road. As to the miles /kilometres accumulation, I've never been bothered to check.
Honda got burned a few years ago with the odometer running over 5% "longer" than reality, so people were complaining about the shortened warranty and the increased maintenance to keep the warranty.
I wonder if some bean counter suggested it?
Honda's were driven by lots of accountant types, so it was probably predictable that someone would check the numbers...
 
Honda got burned a few years ago with the odometer running over 5% "longer" than reality, so people were complaining about the shortened warranty and the increased maintenance to keep the warranty.
I wonder if some bean counter suggested it?
Honda's were driven by lots of accountant types, so it was probably predictable that someone would check the numbers...
Ralph Nader complained about this (pre-Honda, of course, but applying to the Big Three) back in Unsafe At Any Speed. The advantages to the manufacturers included:

-The mileage portion of the warranty expired more quickly.
- Owners thought the car was getting more miles to the gallon.
- Owners thought the car was lasting more miles than it actually was.
 
@Patman, I agree that the actual value in miles should be 162,619, based on the true conversion figure of 0.62137119.

The conversion figure I've always used for short is 0.621, which coincidentally rounds to 162,553.

It looks like Honda decided to go with only three significant figures, which for all practical purposes gets one pretty close.
 
@Patman, I agree that the actual value in miles should be 162,619, based on the true conversion figure of 0.62137119.

The conversion figure I've always used for short is 0.621, which coincidentally rounds to 162,553.

It looks like Honda decided to go with only three significant figures, which for all practical purposes gets one pretty close.

Very very very close.
If I were to overfill my oil, during an oil change, by say 0.003% I'd consider that perfect.
 
I know it’s being really picky but my 2016 Civic doesn’t convert into miles as accurately as I feel it should. Yesterday when I did my oil change the odometer was reading 261,711 km and when I switched the display over to miles it converted to 162,553 miles. But if you do a proper calculation into miles (multiply by 0.6213712) the actual miles is 162,619. I haven’t double checked the Corvette to see if it’s any more accurate than this.

What kind of accuracy are you guys seeing with your vehicles?
I think Honda had a recall for this a few years ago as some Canadian drivers noticed this while changing between mph/kph. I'd call a local dealership to see if it can be recalibrated. This topic comes up alot on Honda forums.
 
It looks like Honda decided to go with only three significant figures, which for all practical purposes gets one pretty close.
Odd thought: if they are using only 3 digits, is the conversion of wheel revolutions to km also wrong? Is Patman's 261,711km really 261,711, or is off by up to 0.5%? [I'm probably using wrong math--I'm thinking, if the right conversion factor is xxx +/-0.5, then it ranges from 0.5% to 0.05%, depending on the value that xxx is. Right?]
 
Odd thought: if they are using only 3 digits, is the conversion of wheel revolutions to km also wrong? Is Patman's 261,711km really 261,711, or is off by up to 0.5%? [I'm probably using wrong math--I'm thinking, if the right conversion factor is xxx +/-0.5, then it ranges from 0.5% to 0.05%, depending on the value that xxx is. Right?]
And another odd thought - given that Hondas are sold around the world, and are engineered (I believe) in Japan, perhaps the kilometers are dead-on (based on new factory tires inflated to factory specs) and it's the miles that are slightly off. It's too small a difference to measure in a non-lab setting.

There are 10 km odometer test sections on the TransCanada highway both E and W of here. I typically take note of the trip meter at the starting point, and look for it to rack up 10.0 km. (If it racks up only 9.9 km, the odometer is running 1% slow. If it racks up 10.2 km, it's running 2% fast.)

If I could switch to miles, I'd look for 6.2. A difference that small (that is, the very small difference between mild and km @Patman sees) would not show up on a modern odometer which increments in tenths of miles or km.
 
It is actually funny to me, that someone would even notice that teeny tiny little bit off the odometer is. If I were to buy new tires for my trucks, that use a 24.5 by 11, and i measured one, and found it was 24.501, by 11.01, I would not give a crap.
 
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