I Seem to be getting a bit worse miles out of my 97 sti, can it be down to a faulty MAF or is it the Lambda sensor that ruins mpg?

 

S'funny but my mpg has nosedived recently, had MAF checked, and cleaned the air filter too.... no better.

Only difference is added Millers octane booster to the last two tank fulls of V-Power.... must be cold weather an shortish trips to/from work.

Or is it oxygen sensor on the way out ?

DunxC

 

usually its the lambda that causes bad mpg, failing maf usually improves it. might not be either though there is a tread on here somewhere about worse mpg in our current cold conditions.

 

Was wondering if it could be cold weather? I work night shift and finish around 5, and at that time for the last two weeks it's been about -5. Cold starting at that temp cant be good for fuel econemy or is it just the same hot or cold? Anyone else think it could be this?

 

colder weather gets my vote

colder more dense air in to engine would mean increased fuelling.

 

Ah maybe explains it then. Bring on the warmer times lol!

 

colder air allows more fuel resulting in more power !! sod the the fuel consumption enjoy the drive

 

bought the wrong car to be looking at the fuel gauge,enjoy it

 

Does perform better through the night mind you at freezing temps, and at that time no traffic .

 

Yep when im on nights i take the long way home at between 5-6am......