General Over-enthusiastic tachometer?

[RobinPJ]

Hi

Our week-old 500 appears to be reading significantly more miles than we think we have driven. Assuming neither of our children are sneaking out to drive the car at night (unlikely as they are 11 and 7) it seems that the tachometer might be wrongly calibrated or something.

Obviously this is a dealer warranty issue (unless we are both just rubbish at guessing distances - I'll do a more scientific check on the weekend) but I'm curious if anyone else has experienced this. A search on the site didn't throw up any previous threads so I'm guessing not...

 

[jrkitching]

Intriguing. Do you think the speedometer is similarly afflicted? Both could be calibrated against a satnav, if you have one. Look forward to hearing more.

 

[Funky Spike]

Is it possible you have it set on KM?

Spike

 

[306maxi]

Is it possible you have it set on KM?

Spike

I'd bet it's that

 

[RobinPJ]

Good answers, thank you, but:

1, No, the speed feels right.

2, after the number of miles/kms it says "Mi" (presumably miles!).

 

[RobinPJ]

I'd bet it's that

That was my initial assumption too!

 

[306maxi]

How overenthusiastic do you think it is?

 

[RobinPJ]

About double - but 8/5ths sounds right, so maybe it is reading kms but saying it is miles.

 

[306maxi]

About double - but 8/5ths sounds right, so maybe it is reading kms but saying it is miles.

Perhaps it's time to go out for a drive on a route you know the length of from google maps (maybe 10 miles) and see what it says. I really doubt there's a fault with the car but never say never

 

[ukmike2010]

Does it also affect the fuel consumption? If its telling you something like 100 mpg the likelihood is that its wrong!

 

[trphil]

Ours seems OK, it's 1.2 miles from Tescos petrol station home in all the cars I've ever done it in! So not a general problem!

Also, of course, you mean odometer not tachometer!

 

[RobinPJ]

you mean odometer not tachometer!

Do I? Actually I was confused - odometer, tachometer, milometer (mlieometer?)...

I have tried swapping to kms then back and it definitely knows the difference. Definitely time to use google maps and plan a route I think.

PS The consumption seems ok so it must be very specific if it is a fault - but then with lectronically controlled cars that is possible in a way that it might not be in "the good old days".

 

[306maxi]

Do I? Actually I was confused - odometer, tachometer, milometer (mlieometer?)...

I have tried swapping to kms then back and it definitely knows the difference. Definitely time to use google maps and plan a route I think.

PS The consumption seems ok so it must be very specific if it is a fault - but then with lectronically controlled cars that is possible in a way that it might not be in "the good old days".

I suspect you're just noticing the miles a bit more because you're starting from 0

 

[jrkitching]

Getting the percentage error as accurately as possible just might help to diagnose this. When you do your calibration check drive, I suggest you also compare the readings on both trip computers, which will give you the first decimal point as well.