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57mpg to 32mpg

Posted: Sun Jan 05, 2014 2:13 am
by chrispy.
Hi

When I got my car second hand from Huddersfield VW, on way home i was doing 80mph down the A12 getting 57mpg. Now if i do 80mph, i get 32mpg
Would this be because it needs a service? Or is there something else?

Re: 57mpg to 32mpg

Posted: Sun Jan 05, 2014 8:20 am
by rover220
I wouldnt rely on the dash readout. Not accurate in the slightest.

Re: 57mpg to 32mpg

Posted: Sun Jan 05, 2014 9:35 am
by john.p.clegg
I just hope plod is not reading this....sounds like a confession...

John :wink:

Re: 57mpg to 32mpg

Posted: Sun Jan 05, 2014 10:12 pm
by alexperkins
What engine? The tdis suffer from egr issues causing low mpg

57mpg to 32mpg

Posted: Mon Jan 06, 2014 6:25 am
by chrispy.
I have the 1.2 TSI
Also, ive gone from £25 = 250 miles to £25 = 200 miles.

Just wondering if its because its due a service?

Re: 57mpg to 32mpg

Posted: Mon Jan 06, 2014 8:30 am
by AJ_7
Have you recently had new tyres fitted?

57mpg to 32mpg

Posted: Mon Jan 06, 2014 12:59 pm
by chrispy.
Nope same tyres since i got the car in May 2013.

Re: 57mpg to 32mpg

Posted: Mon Jan 06, 2014 1:02 pm
by Mart!n-GTI-DK
It's not uncommon that the mpg's drop when it's cold...

Re: 57mpg to 32mpg

Posted: Mon Jan 06, 2014 1:56 pm
by vc-10
Check the tyre pressures too. If they're low it causes more resistance as the tyre deforms more. Not good for the tyre either!

57mpg to 32mpg

Posted: Mon Jan 06, 2014 7:04 pm
by chrispy.
Hmm ill have a look. Thanks for the answers guys!

Re: 57mpg to 32mpg

Posted: Tue Jan 14, 2014 7:25 am
by john.p.clegg
Martin
"It's not uncommon that the mpg's drop when it's cold..."after the disaster of my wishbone bushes, my MPG reduced from 40 to 35 and I thought proper bushes/new tyres and tracking would sort it,but,the last tankful still gave 35 mpg....now my understanding of it is that the Lambda sensor gives info to the engine management unit to correct the air/fuel mixture..the air when colder is denser so one needs more fuel..but no extra power is needed if driven the same way,so less throttle... so why "It's not uncommon that the mpg's drop when it's cold..."

Thanks
John :?

Re: 57mpg to 32mpg

Posted: Tue Jan 14, 2014 7:32 pm
by rover220
john.p.clegg wrote:Martin
"It's not uncommon that the mpg's drop when it's cold..."after the disaster of my wishbone bushes, my MPG reduced from 40 to 35 and I thought proper bushes/new tyres and tracking would sort it,but,the last tankful still gave 35 mpg....now my understanding of it is that the Lambda sensor gives info to the engine management unit to correct the air/fuel mixture..the air when colder is denser so one needs more fuel..but no extra power is needed if driven the same way,so less throttle... so why "It's not uncommon that the mpg's drop when it's cold..."

Thanks
John :?
engines take much longer to get to their most efficient

Re: 57mpg to 32mpg

Posted: Tue Jan 14, 2014 8:14 pm
by RUM4MO
rover220 wrote:engines take much longer to get to their most efficient
Exactly, if anyone is brave/stupid enough, try switching the fan or A/C off a cold morning until you think the car engine is warm/hot - maybe two miles, then switch fan or A/C back on, at the end of that journey you should expect a substantial improvement in that journey's MPG over same journey/conditions with the fan or A/C running from engine start. I live up North and I've been doing that while using my daughter's 6J Ibiza - just to boast about the MPG that I can get on my commute to work.