Low Fuel Economy

[Fastlife91]

I have a 2006 mk2 focus sport 1.8 TDCI

Written mpg is

Urban - 39.2 mpg

Extra urban - 62.1 mpg

Combined - 52.3 mpg

When I fill my tank to the brim and after it has clicked several times I only seem to reach 15 miles until the fuel needle moves from full, that's when I'm driving carefully too. On motorways when driving around 60 mph I only seem to get 20 miles until needle moves from full. On my previous PETROL cars' the needle wouldn't move from full until after driving about 70 - 80 miles.

I also notice that even though I drive very economically that by the time the needle hits half way from full I have usually only driven 170 - 180 miles . I would probably think that rather poor or maybe acceptable for a petrol but I consider that bad for a diesel with the written mpg that mine gets.

I have had the EGR + manifold Replaced a few months back costing £400 because it was faulty but I hoped that would see better mpg but seems not.

Any ideas ????????

I would really appreciate any help, I got rid of my previous car that I really liked because it was petrol and heavy on fuel, I spent £3500 on repairs and a valve went in the engine but I would have gotten it fixed had it not been for poor mpg so I bought this car with much better mpg statically but I'm very disappointed of how it is in fuel ATM.

I have bad connection to my wiring to maf sensor as wires were cut and it needs repairing and engine light on reading maf open circuit a, so I am aware my mpg will be reduced somewhat by this but surely this alone won't be causing such poor mpg ?

Please help

[Russ]

You will never achieve the figures, a quick Google will explain why! Click the link below...

http://www.dft.gov.uk/vca/fcb/the-fuel-consumption-testing-scheme.asp

[Fastlife91]

You will never achieve the figures, a quick Google will explain why! Click the link below...http://www.dft.gov.uk/vca/fcb/the-fuel-consumption-testing-scheme.asp

I know that a car will not achieve the written mpg statistics and so I understand that maybe 8 mpg less or so

But my car seems to be getting 20 mpg less than written statistics, that can not be right

[Russ]

Look at the link, the tests are done in a laboratory over a short distance ie 4 km so 20mpg less is not unusual.

[Fastlife91]

Look at the link, the tests are done in a laboratory over a short distance ie 4 km so 20mpg less is not unusual.

How many miles do you get out of a full tank approx ? Diesel or petrol

If its diesel we have same car

[Russ]

I have a petrol 1.6 titanium mk2 facelift. My drive is normally 7 miles to work and 7 back and I get around 400-410 from a tank before refuelling as I never run it till the light comes on.

[iantt]

Never rely on the fuel guage for calculating how much fuel you have used. Refill and do your calcs that way. Lots of variables affect fuel consumption.

[AdeMk1]

You will be surprised how much difference a faulty MAF, or wiring in your case, can affect economy.

Going from your previous posts you have had this wiring problem for a while now, it's definately not helping your situation so getting the wiring fixed should be your first priority, then see what your MPG figures are like.

[Fastlife91]

You will be surprised how much difference a faulty MAF, or wiring in your case, can affect economy.

Going from your previous posts you have had this wiring problem for a while now, it's definately not helping your situation so getting the wiring fixed should be your first priority, then see what your MPG figures are like.

Hi, thanks for advice

I am hoping to get this wiring issue resolved within the next month or 2, my friend who cut the wires is supposed to be working on it but he is taking far too long to fix it, he often asks me to go up at stupid hours such as 11 pm and has me standing around all hours of the morning as he runs his own mechanics from his house, he just works on his own as a self employed mechanic from home but he usually works on cars all day and night and early hours of the morning.

I am thinking of booking it in with an auto electrician instead now, I had it booked in several weeks ago but I cancelled because my friend said he had just figured out how to fix it, so I cancelled the booking only for my friend to get it wrong again.

Before my friend cut the wires there were 6 wires going to my maf sensor ( previous maf had 6 metal prongs for wires) but after he cut them he put a different maf sensor on my car but the sensor that he put on which is currently the sensor I'm using now only has 4 metal prongs on it, so he looped 2 of the wires and connected 4 to the replacement sensor and the other 2 instead of going to plug ( replacement sensor only holds 4 wires anyway) he just put them into a loop.

He said the 2 wires that he looped were not needed and basically that they were serving no purpose so he later cut off the 2 wires that he had looped.

The reason the wires were cut on my car was because car was taking a while to rev when accelerating and was running rather poor and the engine light was on which read open circuit a or maf range performance so we checked the wires to find the ends of them were torn, so he cut the ends off

can you give me any advice/input on anything I have wrote here ?

Thanks Again

[iantt]

Could be the wrong maf is causing your issues. There are 2 maf sensors, up to aug 2006 build, and after aug 2006, wired up sl7ghtly differentm but both only actually use 4 wires. You may have 6 wires on old plug but looks like 2 did nothing.

Only difference is a ground to pcm on old was pin 5 and later uses pin 6.

As your sensor only has 4 pins then sensor isnt off a 1.8 tdci

[Fastlife91]

Could be the wrong maf is causing your issues. There are 2 maf sensors, up to aug 2006 build, and after aug 2006, wired up sl7ghtly differentm but both only actually use 4 wires. You may have 6 wires on old plug but looks like 2 did nothing.

Only difference is a ground to pcm on old was pin 5 and later uses pin 6.

As your sensor only has 4 pins then sensor isnt off a 1.8 tdci

Hi

Thanks for advice

As I said, originally the maf sensor on my car had 6 wires going to it but after he cut wires and reconnected the maf sensor with 6 prongs it was still running bad which I assume was because he cut the wires and hadn't finished the job due to lack of wire to solder on, he took off the original maf sensor with 6 wires going to it and put on anothet maf sensor with only 4 wires going to it which is the one currently on my car.

He looped 2 of the wires later cutting them saying they weren't needed, is he right or should he have not cut them ?

Now he says we should reconnect original maf with the 6 prongs onto my car ( though it only has 4 wires now) as he keeps swapping the colors of the wires over and doesn't know which one goes were, now he says he thinks he knows which color goes where and says he now thinks putting the original maf sensor back on will fix it ?