Ask Honest John

Most recently answered additives questions
Why will no one do an in-depth review on supermarket v/s the big four fuel suppliers? I am a tanker driver (not fuel) and over the years have asked at least six fuel tanker drivers if there is a difference...
I have a problem with my 2011 Ford Focus 1.6TDCI (old model). When first purchased it gave me 54mpg. 14 months later it has now reduced to 47mpg with the same sort of driving pattern. I have tried to add...
We are focusing on news regarding fuel additives for use in diesel engines. With diesel cars now over 50 per cent market share in the UK, and very significant numbers in use, there's a valid story concerning...
I have followed with interest your comments on DPF problems. I have not experienced these with my own 2009 Volkswagen 2.0-litre turbodiesel, although at 8000 per year I still avoid too many short runs....
My daughter has a 2004 Ford Ka. It has developed an intermittent fault whereby it will often over-rev when idling or rev in "pulses" as if someone is fanning the throttle. It has now also started running...
My daughter has a 2004 Ford Ka. It has developed an intermittent fault whereby it will often over-rev when idling or rev in "pulses", as if someone is fanning the throttle. It has now also started running...
I noticed in your column at the weekend some advice to someone about a judder and an autobox oil change. This is becoming a more frequent problem in the Discovery 3. Dealers will do a double flush of the...
We are the proud owners of a 20-year-old Audi 80 TDI (bought from new), now with 174,000 on the clock. Over the past year it's lost much of it's pulling power. It struggles with even the slightest inclines...
When I looked up the Platinum Plus additive on Google it threw up several other additives also. All claimed to decrease fuel consumption, give smoother running and aid the DPF. Those mentioned were; Millers...
My Jaguar XF 3.0D kept coming up "restricted performance" and yes I have been using it for short runs. However, I got a bottle Forte turbo cleaner and a bottle DPF cleaner and put them in the fuel tank...