vectra 150 cdti mpg

**robk6112** · 12th October 2011, 12:06

Right everyone i dont know whats going on with my latest 07 plate 150 sri as its only getting 39 mpg combined. I have just sold a 54 plate with 138k on compared to 87k on the latest one, both are running the same tuning box which but the 54 plate averaged 53 mpg combined and was quite a bit quicker? THe only diffrences are as followed the old car had a k and n panel filter and a deristricted airbox and had 18 inch wheels compared to the 19 inch?

No warnings are on the dash?

**chewy71** · 12th October 2011, 12:32

I don't think the air filter or air box mod will make any difference (noticable) to your mpg. 39mpg is way too low. Im returning 58 mpg while driving on A roads and a bit of town driving.
Has it had a good service? Re-set the average mpg and see what a weeks driving gives you... unless you've already done that?

**JamesGTB** · 12th October 2011, 12:45

Originally Posted by robk6112

Right everyone i dont know whats going on with my latest 07 plate 150 sri as its only getting 39 mpg combined. I have just sold a 54 plate with 138k on compared to 87k on the latest one, both are running the same tuning box which but the 54 plate averaged 53 mpg combined and was quite a bit quicker? THe only diffrences are as followed the old car had a k and n panel filter and a deristricted airbox and had 18 inch wheels compared to the 19 inch?

No warnings are on the dash?

I would give the Boost Sensor & EGR valve a good clean - this worked for me and gained back better MPG and a much more responsive car - Both jobs take about 20mins total to do.

**Henry42** · 12th October 2011, 12:53

Having the same probelm 07 150 cdti, only getting 38.9 at best, mainly city driving though? this seem right?

**chewy71** · 12th October 2011, 13:30

I'd say 39mpg for city driving would not be far off.

**bingo999** · 12th October 2011, 15:13

just blank the egr off. that improved my economy

**MadOnVaux!** · 12th October 2011, 16:16

Weve just been on holiday upto Scotland in my Dads CDTi 150 Elite estate manual.....fully laiden (3 adults and full boot) it averaged 50mpg.....and urban driving it never drops below 38mpg.

Had a run over to the north east a few months ago and it averaged 55mpg.

**amand** · 12th October 2011, 17:35

Lucky you lot, I'm still getting 32mp on average and its all mixed driving, town, motorway, dual carriage way. 400 on a full tank most of the time.

**Hideous** · 12th October 2011, 18:27

if any of you averaging 39 mpg have the AUTO box, that's normal. it's thirsty compared to the manual, uses about 9mpg more on average.

**Henry42** · 12th October 2011, 19:08

Originally Posted by Hideous

if any of you averaging 39 mpg have the AUTO box, that's normal. it's thirsty compared to the manual, uses about 9mpg more on average.

Mines not auto! Been bugging me for last month or so and been watching how many miles I'm getting for my money, figures are as follows..,,..,

£20 got me 136.9 miles
£25 got me 177.6 miles
£10 got me 123.5 miles

Any ideas this is seems average?