And you are also correct in saying its an average use. I averaged 130:1, the weather was good so I went faster.
which you could argue makes the etec cheaper to run than the 4's
The sum could read
100hrs @ "X" Litres fuel per hr
divide fuel used by 100:1
divide fuel used by 130:1
divide fuel used by 150:1
which ever you prefer
100 hrs being the service interval for a 4 banger x 3 services + filters + oil + cost of 1 major service (this includes 2 DIY services)
an etec is 300 hrs = 1 service + oil used.
adjust this to suit guys
someone get back to me as all available memory has been used