Hello Peeps. I seem to have a problem with our new purchase. We have not had the bongo long so have not noticed this till we went on a long run. I filled the tank £80 and only got 159 miles 14 gallon tank that equates to 11.35 miles to the gallon

We also have a big power loss until the rev counter hits 3500 rpm and then takes off like a scalded cat. I'm thinking that I have a problem with the turbo actuator or waste gate? Driving normally and accelerating below 3500 rpm when the turbo seems to kick in there is an awful lot of black smoke to the point where it is staining the rear bumper and tailgate.
Any ideas??
Thanks in advance