MK5 Golf GTI

All Things Mk5 => Mk5 General Area => Topic started by: mrggg on July 19, 2015, 03:54:37 pm

Title: MPG Loss
Post by: mrggg on July 19, 2015, 03:54:37 pm: Hi, I've had a loss of MPG recently, car was serviced around 1000 miles ago. Tyre pressures are correct, i.e 38psi front and 36psi rear. Although Spark plugs havent been changed for 30k miles...

It maybe the incrase in fuel price recently, but I also dont see the amount of fuel increasing on the computer like it used to. For example travelling at 70mph and the computer reads 130 miles it used to go up to 135 etc, if you get what I mean?

Aside from the spark plugs being the possible culrpit what else could I change? I have already reset the average and recent MPG by pressing ok on the stalk.

Thank you.
Title: Re: MPG Loss
Post by: Carpy25 on July 19, 2015, 09:49:22 pm: A very common problem is the rear brakes dragging that will make a hell of I difference to your MPG

Rob
Title: Re: MPG Loss
Post by: mrggg on July 20, 2015, 05:17:36 pm: Quote from: Carpy25 on July 19, 2015, 09:49:22 pm
A very common problem is the rear brakes dragging that will make a hell of I difference to your MPG

Rob

Thank you. Should I pay the garage £40 diagnostic to fix this? How hard is this to fix?
Title: Re: MPG Loss
Post by: Nino on July 20, 2015, 05:30:15 pm: Your tyres seems incorrect, open you petrol cap I think its set to 32PSI all round?
Title: Re: MPG Loss
Post by: Scottymon on July 20, 2015, 05:33:43 pm: I had the same about 2 years ago, the rear calipers were binding, so I replaced them with some Mk6 callys (because they were low milage and cheap enough) be fine ever since.
The Mk5 rear Calipers are actually lighter than the Mk6, so I'd grab the Mk5's personally.

That aside, have you ever checked your cam follower?
What fuel do you use?
Any air leaks?
Can someone scan the car for beer tokens?
Title: Re: MPG Loss
Post by: Carpy25 on July 20, 2015, 08:58:34 pm: Quote from: mrggg on July 20, 2015, 05:17:36 pm
Quote from: Carpy25 on July 19, 2015, 09:49:22 pm
A very common problem is the rear brakes dragging that will make a hell of I difference to your MPG

Rob

Thank you. Should I pay the garage £40 diagnostic to fix this? How hard is this to fix?

go for a short drive if their binding you should feel that one is hotter than the other side ( its not likely that both are sticking the same time ), don't touch the disc it will burn you just holding your hand close is enough , the wheel my even feel warm

Rob

Rob
Title: Re: MPG Loss
Post by: Scottymon on July 21, 2015, 02:39:18 pm: ^ As above, good idea.
When I replaced the discs and pads on the old Yaris that had been sitting for a year or so, the front caliper had stuck on the offside front... that thing got absolutely nuclear hot just going down the lane, so defo watch your hands.

The rear springs had also snapped on that, causing it to drag a bit. : P
(https://www.mk5golfgti.co.uk/forum/proxy.php?request=http%3A%2F%2Fwww.voodish.co.uk%2Fmisc%2Fboy-racer.jpg&hash=9570ff61c75793318d5ac9b904d960a6bb960414)
Title: Re: MPG Loss
Post by: ephemeross on July 21, 2015, 06:39:43 pm: I had an issue on my old MK4 with the MPG dropping, turned out the MAF & Lambda sensors needed changing.