New Mpg?

[Paulus17]

Hello all hope you are all well.

I don't go in Mrs Ps Rav much so when i did go out in it over the weekend i thought i would check the trip reading on the OBC which i haven't lookedat for ages and was surprised when it was saying 34.5mpg.this has gone up from 29-31 from when we first had the Rav and i was checking it on a regular basis.

Now i know that these figures aren't all that accurate on some Ravs but none the less it is still an improvement,isn't it

[BeechCustom]

The OBC on my 2000 VVTi is, in my experience, actually pessimistic. Last fill up OCD was 28.6mpg, actual (using brim to brim method) was 29.1mpg. I do mostly city driving so 30mpg+ is never going to happen!

[firemac]

Hello all hope you are all well.

I don't go in Mrs Ps Rav much so when i did go out in it over the weekend i thought i would check the trip reading on the OBC which i haven't lookedat for ages and was surprised when it was saying 34.5mpg.this has gone up from 29-31 from when we first had the Rav and i was checking it on a regular basis.

Now i know that these figures aren't all that accurate on some Ravs but none the less it is still an improvement,isn't it

Hi Paul,

The OBC on our 5-dr 4.2 was dead accurate against brim-to-brim calcs whilst the 3-dr was about 10-15% optimistic. You might find that, if you do a couple of brim-to-brims & compare to OBC, that the results are similar - or not. But al least you will then know how much you need to adjust the OBC readings by in future.

In any event, an improvement on the OBC over time is still an improvement. A brim-to-brim calc will confirm how much of an improvement it really is.

[Paulus17]

Hello all hope you are all well.

I don't go in Mrs Ps Rav much so when i did go out in it over the weekend i thought i would check the trip reading on the OBC which i haven't lookedat for ages and was surprised when it was saying 34.5mpg.this has gone up from 29-31 from when we first had the Rav and i was checking it on a regular basis.

Now i know that these figures aren't all that accurate on some Ravs but none the less it is still an improvement,isn't it

Hi Paul,

The OBC on our 5-dr 4.2 was dead accurate against brim-to-brim calcs whilst the 3-dr was about 10-15% optimistic. You might find that, if you do a couple of brim-to-brims & compare to OBC, that the results are similar - or not. But al least you will then know how much you need to adjust the OBC readings by in future.

In any event, an improvement on the OBC over time is still an improvement. A brim-to-brim calc will confirm how much of an improvement it really is.

Yes i used to do the brim to brim tests when we first had it and it was returning anything from 24-28mpg,whereas the OBC was saying 29-31 from what i can remember,think it hit 32 once??

So was hopeful that the mpg had increased as it had increased on the OBC and was wondering what could have caused this??

Mrs P does the same journey to and from work and in fact because of the Brum airport extension her journey has increased slightly.

Looks like the B2B will have to be done again me thinks

[dwilson]

I always fill until the first click on the fuel pump and then enter the results into Fuelly. The OBC often suggests slightly more mpg but occasionally it is the other way around! However the Fuelly average of 30mpg is reliable. What I should really do is not reset the OBC after each fill up but keep it going over several fill ups to get a more reliable average and compare with the brim to brim Fuelly figures.

Lots of variables will affect the mpg including the outside temperature and how much start stop driving is encountered.

David

[firemac]

Hello all hope you are all well.

I don't go in Mrs Ps Rav much so when i did go out in it over the weekend i thought i would check the trip reading on the OBC which i haven't lookedat for ages and was surprised when it was saying 34.5mpg.this has gone up from 29-31 from when we first had the Rav and i was checking it on a regular basis.

Now i know that these figures aren't all that accurate on some Ravs but none the less it is still an improvement,isn't it

Hi Paul,

The OBC on our 5-dr 4.2 was dead accurate against brim-to-brim calcs whilst the 3-dr was about 10-15% optimistic. You might find that, if you do a couple of brim-to-brims & compare to OBC, that the results are similar - or not. But al least you will then know how much you need to adjust the OBC readings by in future.

In any event, an improvement on the OBC over time is still an improvement. A brim-to-brim calc will confirm how much of an improvement it really is.

Yes i used to do the brim to brim tests when we first had it and it was returning anything from 24-28mpg,whereas the OBC was saying 29-31 from what i can remember,think it hit 32 once??

So was hopeful that the mpg had increased as it had increased on the OBC and was wondering what could have caused this??

Mrs P does the same journey to and from work and in fact because of the Brum airport extension her journey has increased slightly.

Looks like the B2B will have to be done again me thinks

Depending upon the distance, number of traffic lights, volume of traffic, etc etc etc, the new route may be less onerous than the previous one or it may be that the extra journey distance is allowing the car to run at a more optimum temperature. You'll use more fuel perhaps but with better mpg.

As you say, a B2B check will give a better idea.

[Paulus17]

When we first had the Rav Mrs P tried driving carefully to try get the MPG up but it never really made any difference so just drives her normal way,and the figures stayed the same,both on the OBC and the B2B tests i was doing back then,and since then haven't really took any notice,so was really surprised to see such an increase on the OBC.

David-How would you get an accurae read out from each test if the OBC isn't reset??

[CharlieFarlie]

I have never owned a vehicle that's fuel consumption is not affected by the way it was driven..... Heavy foot equals more fuel I honestly think that is an inescapable fact...

Some OBCs will be reasonably accurate and some will not.... BTB is the only way as many have said...

But if the OBC reading makes you happy then brilliant. !!!! Me I don't even bother to look at them....

[dwilson]

When we first had the Rav Mrs P tried driving carefully to try get the MPG up but it never really made any difference so just drives her normal way,and the figures stayed the same,both on the OBC and the B2B tests i was doing back then,and since then haven't really took any notice,so was really surprised to see such an increase on the OBC.

David-How would you get an accurae read out from each test if the OBC isn't reset??

The short answer is you can't.

I enter all trips on Fuelly using the brim to brim method and that gives me something reasonably reliable for each trip but probably not very accurate. The range on the petrol RAV is short and not wanting to use more than 3/4 of a tank we are filling up after only 200ish miles. Years ago with wider fuel inlets before unleaded I would literally brim the car until I could see the petrol (not so clever if I then parked on a steep incline shortly afterwards). Nowadays I fill until the first click on the pump but I suspect this is not accurate and will depend on the pump sensitivity (and I use different pumps) and how far I have inserted the nozzle. So I doubt that this method is very accurate. However what I do have confidence in is the long term figure that Fuelly gives me as this will average at those fluctuations.

What I don't know is how the long term Fuelly mpg would compare with a long term OBC mpg and so that will be my next mission. I just enjoy numbers and am interested in how accurate the OBC is...I suspect the OBC is pretty good.

David

[CharlieFarlie]

There seems to be times when the OBC is actually quite accurate.... Other times it lies like hell.... I'm not sure why this should be but suspect it's down to driving conditions for the particular tank full.... No weeks driving will I believe produce the exact same figures due to so many variables ...

Ony then long trips up and down the toad doing 720 miles just to get there and back there was close consistency ... And the OBC was within five percent. .... Now doing round the houses trips with no consistency the OBC is so far out its unbelievable.

To be honest I'm not really bothered by the figures anyway as when the gauge shows low I fill it up.... The government after all need our money to spend wisely ......................,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,

[Paulus17]

I have never owned a vehicle that's fuel consumption is not affected by the way it was driven..... Heavy foot equals more fuel I honestly think that is an inescapable fact...

Some OBCs will be reasonably accurate and some will not.... BTB is the only way as many have said...

But if the OBC reading makes you happy then brilliant. !!!! Me I don't even bother to look at them....

Aye Charlie yam aw right there mukka,but Mrs P never wasn't thraping it round to decrease the MPG??.

It showed that her driving style was more or less the same as when she was taking it easy,if you seewhat i mean.