150 mpg dropped a bit.

[16VWarby]

My sisters 150 (79k miles approx) has recently been a bit crap on fuel, the computer shows 38-40 mpg. It got a bit better when it was mapped last weekend but she used to get 45+ out of it regularly.

I service it (oil, fuel filter, clean the K&N panel etc) as it comes due and was last done about 5k ago.

So, I'm going to clean the AFM next but was also thinking whether the DPF could be getting a bit clogged with the short journeys we do over here as it always runs better after shes been across to college with the motorway run.

Im impressed with its power now its been mapped though! Not as fast as my smelly nissan but very good for an aul derv and a possible replacement for my 4mo

Cheers
Nick

[Steve_PD]

Could be the MAF.
Dont have a DPF got a EGR which might be getting blocked also the inlet manifold. might be worth taking both off and cleaning them

[Organisys]

Sure it's not just the colder weather?

 

[Steve_PD]

Cold weather will make it drop about 5mpg

[scarr89]

Cold weather will make it drop about 5mpg

That much really, crickey!

[16VWarby]

Didnt know the cold made it worse, it was in the last couple of months but its only got cold in the last week & lost about 10-15mpg. So i'd best clean the maf & egr methinks.. Cheers Guys

[Gareth F]

Pump up the tyres
Redex in fuel
And pray for warmer weather 

My 130 is running about 52av in the cold 

[16VWarby]

Pump up the tyres
Redex in fuel
And pray for warmer weather 

My 130 is running about 52av in the cold 

My 200 sx is doing 22mpg when i baby it, about 12 when its on the pipe... I wouldnt be mad at 52, infact i'd be ecstatic

[The Doc]

cold weather + MAF?

[Anthony]

Ive cleaned the egr and inlet and fitted a new gen maf and still only get 35 around town and 45 on the motorway at 70/80 from my pd 150 the car is serviced regularly , but still its better than my last car a 350bhp subaru that was between 150 to 180 out of a 55litre tank