accuracy

Quite a few times I've passed those roadside speed indicators and suspected they were a bit oversensitive as they will read 32 - 33 when the speedo is spot on 30. Occasionally they read 30 when the speedo says 25 (ish). Recently I was reviewing some dashcam footage and thought "I'm sure I...

There are many posts on this, but I really cannot believe how inaccurate the trip computer is! I own a 156 1.9 16v JTD, and I'm getting over 500 miles to a full tank of diesel. Acceptable or not? I'm not particularly sure, I think I worked the fuel consumption out to be around 41mpg or...

Have people calibrated the speedo to GPS in theres, if so what kinda % differences are you getting.

I'm rather unimpressed with the SatNav on my 2015 G QVline. It's the Uconnect system. It quite often says "route recalculation" when I've followed its directions exactly, and sometimes has an odd way of describing an approaching roundabout - for example the other day it told me to "turn left"...

I have 17 inch 225 45 17 on my telledials. i know there are threads on this which confirm that this is the right size. But i have a garnier gps that at low speeds reads the same as the speedo but the difference at 100km is about 5-6km and i do constantly overtake even when im on the limit. i...

So how good is it? It says my car has a heated windscreen, heated washers and the alcohol test kit fitted. It certainly hasn't got the test kit, not sure about the others but I've not noticed and heating mesh in the screen ( heated rear screen is listed separately.).

Hi all, As I've only had my Mito for under two weeks, I wanted to check the Mito's trip computer mpg accuracy against a brim test. The trip computer gave me an overall mpg of 62.7 and brim test calculation gave 61.75. Now I think that that is pretty good accuracy for the trip computer - what...

Hi, I'm looking for some specific knowledge about the clocks in the 166. Mine have returned to life after a fault elsewhere in the car was solved but they are in what I can only describe as "default" mode. I am wondering, does the instrument cluster come with an "out of the box" default as a...

Hi Guys, I was wondering if anyone knew how accurate (or inaccurate) the speedo is on the 156 GTA? I was driving today and had my blackberry GPS on. 40 mph on speedo was around 35 mph on GPS. 70 mph on speedo was 62 mph 80 mph on speedo was 72 mph 90 on speedo was 82 mph anyway, makes me...

Hi Guys, I know these things have a fairly poor press re accuracy but wondered if they were consistently optimistic or if it differs from car to car. I've put a few tankfulls through my 20V and it seems to be optimistic by about 12 mpg but pretty consistent. Thus, an indicated 50 mpg resulted...

The trip computer on my 156 Sportback used to be pretty accurate, but at my last re-fill when I re-set for the latest tankfull it started behaving a bit strangely. It now seems to be under-reading the distance by a huge amount, and so it now shows far less mpg! Any ideas to sort it out? I've...

I've commented before on just how accurate the computer seems to be in my car. Well, I've just completed a full year checking the computer mpg v brim-to-brim readings and the average over the year? 30.78 by the computer 30.79 measured brim to brim I find that quite astonishing.

I know that this has been mentioned in the past but worth bringing up again. I have been relatively happy with my mpg in the 3.2, seemed to be the same or a bit better than my 3.0 BUT that was according to the ICS - Calculated it myself after filling up and realised that the ICS is reading 3 to...

I have a 159 1.9jts and recently changed the wheels to 18" with 235/45/18 tyres. I'm a little confused by Alfa because this wheel and tyre combination gives a rolling diameter 4.04% bigger than the standard 16" wheels with 215/55/16 tyres the car was built with. This means that the speedo with...

I find the trip computer(s) on the 159 very useful, but have never checked the accuracy. I did that today at the latest tank refill. The computer reckons I had averaged 40.2mpg over the last 500 miles, but my calculations make it 41mpg. That's close enough for me - anyone else checked the...

Hi pepes Maybe the title is a contradiction of terms or as my new dictionary under the heading "acuracy" said, Incorrect spelling of Accuracy. Any hoo:) does anyone know the +- tolerance for rev meters? My sat nav says that the speedo is reading around 2-3 mph slow at most speeds (apart from...

does anyone know how accurate my speedo will be? bog standard tyres fitted by dealer before we bought it second hand and its done around 36k miles. seen 138 a couple of times and downhill saw 141 (or has it all been a dream officer?) never driven flat out for a few minutes to see if it will...

While enroute to Newcastle and back at the weekend is was alerted by my Garmin to all the fixed and mobile speed traps. Some are well out of date but some were accurate. The problem was the indicated speed on the Sat Nav and the speedo varied according to the speed. At 30 MPH not much in it...

From my last tank of fuel the ICS stated 25 odd to the gallon. I filled up and decided to check consumption the old way (Habit!) - I worked it out as 22 odd MPG. My method should be accurate - I always fill up until pump cuts out, I don't try to force any more in so should be filling back to...

Hi. I filled up today. Covered 339 miles, 59.28L (13.04 gals) of Tesco's finest 97RON. Trip computer stated a healthy 32.2mpg:D When I got home and did the math, it comes out as 26mpg:eek: :mad: To add insult to injury, the reason the changed my speedo (see other general discussion thread)...