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Does anyone actually think their trip computer is accurate
I always assume they lie. I haven’t calculated mine manually for a while though. Oddly the mileage trip on my abarth used to count up at a different rate to the main odometer. So if you reset it at 20000 miles, at 20300 miles the trip would say something like 303.
Does anyone actually think their trip computer is accurate?
I’ve found them close enough not to care about tiny bit it’s off. The VW app seems very accurate though and again close enough for me not to worry about or waste my time with a spreadsheet.
(Toyota Auris 1.6 diesel)
I’ve been around 41-42 mpg per tank recently now it’s winter (have had bike carriers fitted a fair bit too)
Was generally 50-51mpg a tank earlier in the year.
do you just batter round town in that , i'm amazed such a small car gets such a low MPG
surely that should be 60+ mpg ?
Does anyone actually think their trip computer is accurate?
It’s about as accurate as your speedometer, with the added tolerance impact of measuring fuel used.
Oddly the mileage trip on my abarth used to count up at a different rate to the main odometer. So if you reset it at 20000 miles, at 20300 miles the trip would say something like 303.
That is a bit odd, I wouldn’t be surprised at a variable (differs between each trip reset), but fixed for a given trip reset, but would expect it to be be less than 2km. The algorithms for storing odometer distance are more complex than most people imagine due to the need to keep a high precision[1] number, with potentially large values using non-volatile memory that has limited write cycles[2].
[1] Precision and accuracy are not the same thing (wanders back to the pedantry thread)
[2] All NVM has a write cycle limit, for EEPROM its typically 100000 cycles guaranteed, which would only cover the first 10000km at 0.1km resolution.
Our last family car was a 57 plate Mondeo 2.0 TDdci that averaged 48mpg, I could get up to 62mpg on motorway journeys keeping it on the inside line and matching pace with the HGVs
The 64 plate S-max 2.0Tdci that has replaced it has better official Mpg, but only averages around 45mpg, on Motorways it only goes up to 52mpg.
I have an 08 plate Peugeot 107 that I use for my 7 mile commute to work on country roads that refuses to do less than 50mpg.
Does anyone actually think their trip computer is accurate?
I reckon ours are close enough, on the very rare occasion I’ve worked it out they’ve not been far off.
I usually have the computer in mine showing either range or speed, which I find much more useful than mpg.
Jag does 40ish on a run. Low to mid 30’s the rest of the time. I did monitor once to see how accurate it was - seemed to be optimistic by 5-10%.
Weekend toy does 4mpg.
My car lies like a Chinese health official.
64.8 mpg average when the reality is 52or 54 depending on ambients
Always over in my experience, though this volvo is the worst I have had
My M140i has averaged 30.7mpg since I collected it in June which I don’t think is too bad for a 3 litre car.
It’s quite capable of being pretty economical on a decent run but it’s equally adept at making super unleaded vanish pretty quickly if driven hard.
X1 25D 42 mpg mixed on V Power.
Aerodynamics of a brick.
Does anyone actually think their trip computer is accurate?
Mine is yes, I’ve checked it.
On both.
(Toyota Auris 1.6 diesel)
I’ve been around 41-42 mpg per tank recently now it’s winter (have had bike carriers fitted a fair bit too)
Was generally 50-51mpg a tank earlier in the year.
do you just batter round town in that , i’m amazed such a small car gets such a low MPG
surely that should be 60+ mpg ?
Probably a mix of bad traffic and bad driving style. I live in London so my commute is often 15-20 minutes in stop/start traffic, 10 minutes at 75ish, then another 10-15minutes that can be a bit stop/start again.
Best I've seen on a single trip was 74.9 on a short 9 mile journey - through 50mph average speed cameras for most of it and with a warm start.
driving style makes a huge difference even if its an imperceptible difference in style. A good few years back I did a european tour on my BMW r1100rs with a mate with a ZZR1100. Despite the BMW having fuel injection compared to carbs on the ZZR and the BMW being lighter and we both rode at similar speeds ( he was a faster rider than me) he got better MPG and longer out of his tyres. In the end we decided the main factor was he rolled away from a stop gently in first, short shifted to second then opened the taps, I tended to rev much higher in first and with a wide open throttle.
Ruddy annoyed me that his faster more powerful and heavy bike got better MPG and he was faster overall.