Computer Incorrect MPG and average MPH reading

jamescora · 1st March 2007, 12:12

All,

I know we have talked about the MPG reading being incorrect on the Civic. However, mine is out by 5mpg which I think is excessive. On two separate tank fulls I got 41 and 40mpg respectively. However, the computer said I was getting 46 and 45 respectively!!! How can it be so far out.

Also, the average speed is incorrect. It I reset trip A while on cruise control the speed on the speedometer differs from that on the computer by 5mph. I was driving at 63mph last night. flat road, cruise control set. I reset the trip A and after a few seconds a speed of 58mph was registered. It remained at 58mph until I changed speed.

Are the faults related??
Are the faults common??
Am I too fussy???

Geoff13th · 1st March 2007, 12:25

I would say to fussy!!

The two things must be related, now all i need is a strech of motorway thats empty to try the CC and ave speed.....

don't think i ever use the ave speed though, apart from just wondering how quick you were going what is the use of it?

Bungle · 1st March 2007, 12:35

Your odometer (and therefore your ave speed) is correct. It ahs to be. Your speedo over-reads. All of them do. They do it on purpose to ensure they do not under-read (which is illegal) and it also means when you are driving, you are in fact going slightly slower then you think.
Great for those moments when your speed creeps up slightly when you are near a camera.

About your MPG, I'd say, without sounding rude, it is a bit fussy asking for it to be 100% accurate. It is only there to give you an idea of how much fuel is being used, it is not designed to be a preceision instrument.

jamescora · 1st March 2007, 14:00

THanks for your replies guys.

Fair enough.... maybe I am being a bit fussy.
Overall I am absolutely delighted with the car. So glad I bought it rather than a leon or focus.

Also, they are still relatively rare in Eire.

I have one other complaint though....... the styling is far too conservative!!!!!........... joking!!! 80s spaceships are so in right now!!!

l-noel · 1st March 2007, 15:52

Quote:

Originally Posted by jamescora

All,

I know we have talked about the MPG reading being incorrect on the Civic. However, mine is out by 5mpg which I think is excessive. On two separate tank fulls I got 41 and 40mpg respectively. However, the computer said I was getting 46 and 45 respectively!!! How can it be so far out.

Also, the average speed is incorrect. It I reset trip A while on cruise control the speed on the speedometer differs from that on the computer by 5mph. I was driving at 63mph last night. flat road, cruise control set. I reset the trip A and after a few seconds a speed of 58mph was registered. It remained at 58mph until I changed speed.

Are the faults related??
Are the faults common??
Am I too fussy???

Concerning the average speed it's not fussy at all.
The speedometer show a speed above the actual speed (on my car it is 6 km/h witch is about 4 mph it vary from car to another) But Trip A register the main actual main speed. So if you reset the Trip A when you are cruising at 63 it is logical that the average speed is only 58 mph.

Buzby · 3rd March 2007, 09:39

I have just picked up my new Civic ES and so far thrilled however I too have noticed my speedo reading is 4 to 5 mph greater than actual speed I was able to check it against the speed on my tom tom. My jazz which I have just traded gave a spot on mph reading when compared to my tom tom.

I would much prefer the speedo to be accurate is there any way of having it adjusted?

Thanks,

Buzby

1st March 2007, 12:12	#1 (permalink)
jamescora Valve Cap Join Date: 27th December 2006 Location: On the side of a mountain in Wexford, Eire. Posts: 24 Thanks: 0 Thanked 0 Times in 0 Posts iTrader: (0)	Incorrect MPG and average MPH reading All, I know we have talked about the MPG reading being incorrect on the Civic. However, mine is out by 5mpg which I think is excessive. On two separate tank fulls I got 41 and 40mpg respectively. However, the computer said I was getting 46 and 45 respectively!!! How can it be so far out. Also, the average speed is incorrect. It I reset trip A while on cruise control the speed on the speedometer differs from that on the computer by 5mph. I was driving at 63mph last night. flat road, cruise control set. I reset the trip A and after a few seconds a speed of 58mph was registered. It remained at 58mph until I changed speed. Are the faults related?? Are the faults common?? Am I too fussy???

1st March 2007, 14:00	#4 (permalink)
jamescora Valve Cap Join Date: 27th December 2006 Location: On the side of a mountain in Wexford, Eire. Posts: 24 Thanks: 0 Thanked 0 Times in 0 Posts iTrader: (0)	Fair enough THanks for your replies guys. Fair enough.... maybe I am being a bit fussy. Overall I am absolutely delighted with the car. So glad I bought it rather than a leon or focus. Also, they are still relatively rare in Eire. I have one other complaint though....... the styling is far too conservative!!!!!........... joking!!! 80s spaceships are so in right now!!!

3rd March 2007, 09:39	#6 (permalink)
Buzby Supporter Valve Cap Join Date: 16th February 2007 Location: Stockport, Cheshire Posts: 40 Thanks: 1 Thanked 0 Times in 0 Posts iTrader: (0)	Speedometer reading I have just picked up my new Civic ES and so far thrilled however I too have noticed my speedo reading is 4 to 5 mph greater than actual speed I was able to check it against the speed on my tom tom. My jazz which I have just traded gave a spot on mph reading when compared to my tom tom. I would much prefer the speedo to be accurate is there any way of having it adjusted? Thanks, Buzby

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This thread is about: Incorrect MPG and average MPH reading, it's in Bugs, faults and irritations at the Honda Civic forum Civinfo; All, I know we have talked about the MPG reading being incorrect on the Civic. However, mine is out by 5mpg which I think is ...

1st March 2007, 12:25	#2 (permalink)
Geoff13th Wheelnut Join Date: 4th December 2006 Location: Just outside of Luton Posts: 78 Thanks: 0 Thanked 0 Times in 0 Posts iTrader: (0)	I would say to fussy!! The two things must be related, now all i need is a strech of motorway thats empty to try the CC and ave speed..... don't think i ever use the ave speed though, apart from just wondering how quick you were going what is the use of it?

1st March 2007, 12:35	#3 (permalink)
Bungle Rocketship door handle Join Date: 3rd July 2006 Location: SE London/Kent Posts: 1,220 Thanks: 0 Thanked 0 Times in 0 Posts iTrader: (0)	Your odometer (and therefore your ave speed) is correct. It ahs to be. Your speedo over-reads. All of them do. They do it on purpose to ensure they do not under-read (which is illegal) and it also means when you are driving, you are in fact going slightly slower then you think. Great for those moments when your speed creeps up slightly when you are near a camera. About your MPG, I'd say, without sounding rude, it is a bit fussy asking for it to be 100% accurate. It is only there to give you an idea of how much fuel is being used, it is not designed to be a preceision instrument.