strange mpg issue

[hipwell]

Just did a trip down to heartforshire in the 182 on a full tank of vpower.

on the way there the cruise controll was set at bang on 70 all the way there pretty much, think i had to use the clutch about 3 times for the odd roundabout and i averaged 43mpg when i got there.

on the way back i reset the trip as i did on the way there, tank was now half empty so less weight, same 70mph cruise controll all the way back but yet this time i only averaged 36mpg.

Does this suggest that my lambda packed in due to the long journey (its used to doing 2 miles a day)

or that cars use more fuel going north than they do south ?? (joke)

Or something else?

 

[MarkCup]

Traffic density?

How much were you braking on the return journey? Using the brake pedal drinks fuel...

 

[Chip-mk1]

Herts is pretty low (highest point when I just looked it up is only a couple of hundred meters about sea level) so where do you come from, if its somewhere high then you might have had more downhill on the way than on the way back.

Distance you sit from the car in front has an effect, as does if you are driving through puddles which cause more drag.


The MPG reading is pretty moderate in its accuracy anyway though TBH, wouldnt really too much into it, although that said I wouldnt expect that sort of massive difference.

 

[hipwell]

I live in sheffield.

Traffic density was pretty much the same on the way back as it was on the way there, rarely had to press the brake

 

[Chip-mk1]

Similar height start and finish then so sort of rules out gravity, but on the other hand if the hills are long and mild in one direction and short and steep in the other it will effect MPG to.

You really need to do the journey a few times in both directions to get meaningful data.

 

[hipwell]

Yeh ano, itl have to wait another 6 months though untill i next go down to visit my nan, cant afford another 50 quid of fuel lol.

Seems daft, but thinking about it on the way back i was pretty much alone most of the time, wheras on the way down i was cruising behind another car for a good chunk of the journey, but i wouldnt have thought slipstream would have made any difference unless i was really up his arse which i wasnt.

 

[Edges]

I sat behind a lorry for 20 minutes the other day the mpg went up by 0.4. Just thought it might be relevant :/

 

[Dan@SJM]

Its because your heading north, thus uphill pretty much all the way.

 

[john182rs]

You might find you did slightly more distance but also more speeding up and slowing down, so less regular average speed.

Stuff like doing more uphill driving and wind condictions/direction will change it aswell as tyre pressure and many many more factors.

I personally would not worry about 7mpg though.

 

[Paul182]

i cant get any more than 35 no mater how i drive ! i would love to get 43

 

[Alan]

You should be thankful for 35+ in a 2.0L petrol with a 5 speed box IMO.

 

[Chip-mk1]

i cant get any more than 35 no mater how i drive ! i would love to get 43

Phase1 are normally a little better, as they have a taller ratio diff.

 

[hipwell]

i cant get any more than 35 no mater how i drive ! i would love to get 43

i would say theres something up with your car mate, after owning my 182 for 3 years 36 mpg is the first time ive seen it go below 40 on a motorway run doing the legal speed limit.

 

[rftaylor]

i havnt seen over 28mpg in my standard 182! i just think of all the shell points haha, will go to stone in feb when it needs a service.

 

[Paul182]

i would say theres something up with your car mate, after owning my 182 for 3 years 36 mpg is the first time ive seen it go below 40 on a motorway run doing the legal speed limit.

yes was thinking the same. will probably change a few sensors after xmas.