poor economy on 1.8 16V

[leigha 0]

thought it might be for the dash though i was hoping it was a wonder cure!!!

 

earlier i reset it while the engine was warm then drove along like a granny, out of town and i managed to get it to read 27mpg!!!! that's a record!

[bcstudent 0]

I'd ignore it for now and make a point of sorting the clocks out so you can calculate it for definite. It's been said though, 30-35mpg is good!

[leigha 0]

i've got some clocks to fit this weekend so hopefully i'll have good news soon, though the rate i'm filling up seems to indicate all is not that well

[jonnyboyo 0]

Not sure what my valver averages ( G reg with 118,000 miles ) but it has awesome economy! On a run, all motorway, i can do 215 miles on less than half a tank. Its good round town too.

[bcstudent 0]

Not sure what my valver averages ( G reg with 118,000 miles ) but it has awesome economy! On a run, all motorway, i can do 215 miles on less than half a tank. Its good round town too.

That sounds pretty normal to me. The tank isn't perfectly square so fuel usage isn't linear. In my 1.8 16v, around town, I can do almost 70 miles before the gauge even moves off the maximum mark. It still only does 30mpg though.

[jonnyboyo 0]

Yeah i know what you mean bout the guage not moving for ages when on a full tank, but compared to my Celica GT4 i recently flogged, the mileage i'm getting from my ickle Rado is wicked :)

[leigha 0]

ok. the definitive combined economy figures for by car over a 260 mile average are:

22.4mpg according the the MFA (with the milage agreeing with the new odometer)

25.2mpg actualy, measured.

 

this was done by filling the tank to the brim with 95 octane, zeroing off the MFA and tripmeter and driving 260 miles. then refilling to the brim (47 litres).

 

in the standardised units for fuel economy, that's 65 miles to a tenner!

 

that was not including more than 5 miles of spanking and did include a sedate 100 miles on a nice run, keeping to a sensible speed (60 max) with no 'booting it'.

 

does this sound bad then people?

[leigha 0]

i've just got figures for another round-town only tankfull:

MFA indicated 20mpg

calculated 22.5mpg

 

the average speed on this full tankful (according to the mfa) was 17mph so all pretty slow stuff but no real thrashing or anything.

 

i've now refilled with the new shell high octane stuff to see how it fares with the right fuel in there......

[bcstudent 0]

22.5mpg around town sounds about right, but a 25.2mpg average out of town isn't great. I'm not sure what to suggest to be honest.

[leigha 0]

diesel conversion? ;)

 

our other car does about the same mpg but that's a E30 3 series bmw with a fairly bloody pokey 3.5 litre conversion and you have to thrash the tits off it for the mpg to drop that low!!! it's also just a tad quicker ;)

[leigha 0]

right...

i've just reached the end of a tankful of 98 octane and......... no difference! MFA indicated 20.5 mpg, actual 22.8mpg. not great. :(

[A-J 0]

I was reading this thread last week after my MFA went from a reading of 25mpg around town, to 18mpg. By the end of the week it began to deteriorate and dropped as low as 8mpg! For no obvious reason it has returned to the 25ish mark again :?

 

I haven't had the chance to work out the proper figures yet but I don't think they'll be that great and I agree is not what you would expect from a car that isn't that quick.

 

I did notice the amount of fuel I could get in the tank varied quite a bit from one petrol station to the next, possible due to incline or dodgy pumps. This could affect your calculations.

[Jim 1]

Sounds like an attempt at a 'quick fix' but thought about shoving a bottle of injector cleaner in with your next fill up?

[leigha 0]

might be worth a go... i've not done the usual redex trick yet.

 

it's odd as the engine is running well and feels strong but at this level of performance drop i'd expect it to be unhealthy and misbehaving