Author Topic: Fuel Economy Decline  (Read 4715 times)

Offline Sweeney

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Re: Fuel Economy Decline
« Reply #10 on: 16 October 2009, 17:09 »
Checked tyre pressures? Just that you mentioned new boots all round.

Offline Chris MKV

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Re: Fuel Economy Decline
« Reply #11 on: 16 October 2009, 18:01 »
I have noticed that the Gti uses more fuel at exactly the same moterway speeds when it is colder.

I think this is simply due to the car having to push through denser air (do more 'work') and this needs more power which in turn requires the burning of more fuel. :nerd:

I can't see that the engine makes any difference on this - yes an engine can produce more BHP (and so burn more fuel) when running the throttle wide open in cold air but this is unlikely to be the way you drive your commute! :shocked:
I've been a target for 'halfords spec' saxos for almost three years now!

Offline smartypants

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Re: Fuel Economy Decline
« Reply #12 on: 16 October 2009, 23:30 »
Could be right Chris.... its probably just me being over sensitive to the fact that I now have constant read outs to my MPG stats!


Offline monzablue16v

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Re: Fuel Economy Decline
« Reply #13 on: 17 October 2009, 01:10 »
Colder fuel is more dense than warm fuel. Petrol stations tanks are underground and kept at stable temperatures by the earth surronding them at depth. If the surface is cold fuel shrinks as it goes in the tank. less fuel and same amount used by the engine = worse fuel economy. Also goes quicker when it's cold. :evil:
I reckon anyway :)

Probably got lost in the "Great Crash of 08

Offline Khare

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Re: Fuel Economy Decline
« Reply #14 on: 17 October 2009, 01:25 »
gotta love going for a blast when the cold dense fog is at sea level  :evil: :evil: :evil:


Offline smartypants

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Re: Fuel Economy Decline
« Reply #15 on: 26 October 2009, 07:43 »
Right I think I've worked out the problem!!! Just looked under the bonnet for the first time since the cambelt change at the beginning of the month and found this:






I've put it all back in place, doesnt seem too damaged, apart from a screw missing as indicated in the 3rd image. I've not tried the car yet to see if that is definitely the problem, but I am pretty certain it will be! As I said the drop in fuel economy was significant for me to think something was wrong.

I am obviously going to contact Ridgeway Reading (which I will name and shame) who I can blame for this. Is there likely to have been any other adverse affect on the engine whilst it was in this state?




Offline jaydubveedub

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Re: Fuel Economy Decline
« Reply #16 on: 26 October 2009, 08:21 »
That is appalling.

I suggest you go and speak with the service manager and also the dealer principle, plus email the pics/details to VW UK.
2003 Passat 1.9 Sport TDI Wagon | Inky Blue | Lots of Wax

Offline smartypants

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Re: Fuel Economy Decline
« Reply #17 on: 26 October 2009, 09:00 »
That is appalling.

I suggest you go and speak with the service manager and also the dealer principle, plus email the pics/details to VW UK.

Cheers I think I will, I certainly dont want to leave it like that.

My car is currently with Ridgeway Newbury for an MOT - have asked them to look at it to see what damage there is to the unit and screws needed, but not to do the work so I can contact Reading to sort it out.

Offline smartypants

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Re: Fuel Economy Decline
« Reply #18 on: 26 October 2009, 18:52 »
Driven home after my MOT (another £250 robbed off me for a CV boot and headlight adjustment), and since putting the hose back in place, fuel economy is back to "normal" - thankfully!

Now to to write that complaint letter.............

Offline monzablue16v

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Re: Fuel Economy Decline
« Reply #19 on: 26 October 2009, 19:40 »
Wonder what else they bodged?

Probably got lost in the "Great Crash of 08