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I only seem to be getting 38 mpg , mostly urban but with some short extra urban trips

I drive a 2006 mk2 focus sport 1.8 TDCI

my approx. fuel figures

urban. 39.2
extra urban - 64.2
combined - 52.3

I have been driving around 90% urban and 10 % extra urban, some short motorway trips of around 20 miles mixed in and usually going 65 mph on the MW.
I often drive in an eco friendly manner too

But when I use online mpg calculator I only seem to be getting 38 mpg despite the lowest written mpg for my car being 39.2 which is urban only and I don't seem to be getting that , only get around 38 mpg and that is some short motorway trips too.

Usually by the time my fuel gauge gets to half way I am lucky to have covered 200 miles and by the time the fuel light comes on, only around 400 miles


it takes around 43 litres to fill car once light comes on

any ideas ?

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Your driving is the problem.
Reply 2
Original post by Potally_Tissed
Your driving is the problem.


what ?

You don't even know how I drive, so don't criticise me please
Original post by I love life
what ?

You don't even know how I drive, so don't criticise me please


It's one of three things:
1. Your driving is not as fuel efficient as that used in the official test of the vehicles fuel efficiency
2. You suck at maths despite using a calculator
3. Your car is inexplicably really thirsty for some reason

My money is on 1. Achieving the "official" fuel efficiency figures is pretty boring.
Reply 4
39mpg. LOL... cute!

What's under the bonnet a hamster in a wheel?
Original post by JC.
39mpg. LOL... cute!

What's under the bonnet a hamster in a wheel?


Two hamsters, but they're both on a strict diet.
Reply 6
Original post by Potally_Tissed
It's one of three things:
1. Your driving is not as fuel efficient as that used in the official test of the vehicles fuel efficiency
2. You suck at maths despite using a calculator
3. Your car is inexplicably really thirsty for some reason

My money is on 1. Achieving the "official" fuel efficiency figures is pretty boring.

1. I don't always drive as eco friendly as I could but I never drive too aggressively

2. ???????? I am good at maths but I use an online calculator mpg, all it asks for is input for miles driven, cost of refuel or litres, and cost of litres, so easy peasy

3. Well, maybe the damaged mass air flow wiring loom may account for it, it has triggered engine light and I need it fixed asap and need to find wiring harness for it, been like this for months, and maybe a fuel injector or 2 may be at fault.
Original post by JC.
39mpg. LOL... cute!

What's under the bonnet a hamster in a wheel?


what is cute, why is 38 mpg cute ??


and what do you mean by '' a hamster under the bonnet in a wheel ??
Original post by I love life
1. I don't always drive as eco friendly as I could but I never drive too aggressively

2. ???????? I am good at maths but I use an online calculator mpg, all it asks for is input for miles driven, cost of refuel or litres, and cost of litres, so easy peasy

3. Well, maybe the damaged mass air flow wiring loom may account for it, it has triggered engine light and I need it fixed asap and need to find wiring harness for it, been like this for months, and maybe a fuel injector or 2 may be at fault.


what is cute, why is 38 mpg cute ??


and what do you mean by '' a hamster under the bonnet in a wheel ??


1. There you go then, it's your driving, because you apparently do not always drive as eco friendly as you could
2. Quite
3. I don't know what that means. It's probably your driving.

Also, he means that your cars engine has about as much power as a fat guy on a treadmill. Don't take it personally, JC thinks that anyone whose car was built this side of about 1976 or has an engine smaller than 3 litres may as well get out and push.
(edited 8 years ago)
Reply 8
Original post by Potally_Tissed
1. There you go then, it's your driving, because you apparently do not always drive as eco friendly as you could
2. Quite
3. I don't know what that means. It's probably your driving.

Also, he means that your cars engine has about as much power as a fat guy on a treadmill. Don't take it personally, JC thinks that anyone whose car was built this side of about 1976 or has an engine smaller than 3 litres may as well get out and push.



1. no, I sometimes try to drive in a eco friendly way, not because I'm bothered about the environment, more because I want better mpg.
Also when I'm not concentrating on driving in an eco way, I still drive reasonably

2 . ????

3 . do you know what a mass air flow sensor is ? well the wiring loom that connects to the sensor is in a bit of a mess atm, hence triggered engine light on .


Regarding JC- Oh, whatever





anyway, what mpg do you get
Original post by I love life
1. no, I sometimes try to drive in a eco friendly way, not because I'm bothered about the environment, more because I want better mpg.
Also when I'm not concentrating on driving in an eco way, I still drive reasonably

2 . ????

3 . do you know what a mass air flow sensor is ? well the wiring loom that connects to the sensor is in a bit of a mess atm, hence triggered engine light on .


Regarding JC- Oh, whatever





anyway, what mpg do you get


About 46.
Original post by potally_tissed
about 46.


what kind of roads, how aggresive is your right foot ?

Oh, what car and guel type
Original post by I love life
what kind of roads, how aggresive is your right foot ?

Oh, what car and guel type


Total mix. Very. BMW Mini. Petrol.
Reply 12
Original post by Potally_Tissed
1. There you go then, it's your driving, because you apparently do not always drive as eco friendly as you could
2. Quite
3. I don't know what that means. It's probably your driving.

Also, he means that your cars engine has about as much power as a fat guy on a treadmill. Don't take it personally, JC thinks that anyone whose car was built this side of about 1976 or has an engine smaller than 3 litres may as well get out and push.



'79 is my cut off point, barring a few exceptions. :wink:

Lets face it, anything getting more than 30mpg is likely to be a snoozemobile.
Sub 25 is likely to be something interesting. Sub 20 is a propper car and single figures is likely to be seriously impressive.
Original post by JC.
'79 is my cut off point, barring a few exceptions. :wink:

Lets face it, anything getting more than 30mpg is likely to be a snoozemobile.
Sub 25 is likely to be something interesting. Sub 20 is a propper car and single figures is likely to be seriously impressive.


Maybe you only like the older car's because they are a breeze to work on, extremely very easy indeed to work on and maybe modern cars are very very difficult for you to understand and work on
Original post by Potally_Tissed
Total mix. Very. BMW Mini. Petrol.


what the **** is a '' BMW MINI '' ? they are both 2 completely different cars.

And I bet if you did mostly urban then your mppg would drop below 40
You do realise that bmw own mini?
Original post by I love life
what the **** is a '' BMW MINI '' ? they are both 2 completely different cars.

And I bet if you did mostly urban then your mppg would drop below 40


I mean the new style Mini which is in fact owned by (but not badged as) BMW, as opposed to the old style Austin Mini.
Fix your MAF. Your economy will probably improve.

With the MAF broken or malfunctioning, the ECU will often revert to a 'safe' air flow map, which reins in the engine somewhat and kills both power and economy to protect the engine as the ECU is essentially calculating fuelling blind. This probably also explains your cars inability to top 70mph.

You need to get your car in correct working order before worrying about things like economy.
Original post by Nuffles
Fix your MAF. Your economy will probably improve.

With the MAF broken or malfunctioning, the ECU will often revert to a 'safe' air flow map, which reins in the engine somewhat and kills both power and economy to protect the engine as the ECU is essentially calculating fuelling blind. This probably also explains your cars inability to top 70mph.

You need to get your car in correct working order before worrying about things like economy.


Hi

Thanks for your kind answer.

I have just started saving up again so that I can take it to an auto electrician, it will probably be 2 months until I can save up £400 or so to take it in, hopefully it will cost no more than £400, any less would be good.
I hope my mpg will improve once the wiring is fixed and I certainly hope it provides more power than what it is giving atm.


I realized lately, it's not just when trying to top 70 mph, overtaking on the motorway for example, it seems to be whenever I rev it hard, even at 30 mph or 40 mph when revving hard to get up a hill, to overtake or anything at any speed, when you rev hard it does it, you can very quietly hear like a little tap noise under bonnet when driving, then it refuses to accelerate or accelerates very slow and feels sluggish. then if you turn engine off and back on to reset itself it feels fine again until you rev it too hard.
This symptom occurred for the first time about 20 minutes after Brian cut the wires, I was on the motorway driving home and it happened then, so it is connected to the wires being cut and messed up.

I have questions, would you please be so kind as to answer for me.

A. how much do you think it would cost an auto electrician to resolve this issue ? ( I know you don't know, but just what you think )

B. Brian took off original 6 pin sensor and put a 4 pin sensor on my car, now I want to put original 6 pin sensor back on my car but where can I get a plug from to put original 6 pin sensor back on ? Brian cut off the 2 wires that he called open loop and said they were not needed, the new plug I will get needs to have 6 wires on it to connect back to the original sensor.

C. will my mpg and power improve noticeably when it is fixed?

D. How does the engine stop the accelerating when revved to hard due to cut wires ?




Thank you so much
Reply 19
Original post by I love life
Maybe you only like the older car's because they are a breeze to work on, extremely very easy indeed to work on and maybe modern cars are very very difficult for you to understand and work on


You *might* be right...
But then again... when I owned a Focus I didn't have to post 10 threads a day asking for advice on how to mend it. I just um... fixed it quietly and got on with life. :wink:

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