Ask Honest John

Most recently answered premium fuels questions
Why do you think my wife's Hyundai Getz 1.4 CDX automatic is giving such poor mpg? It averages just 27mpg and although it is only used around town we are disappointed. It is a 2007 car, has 11,000 miles...
I bought a Ford C-Max 1.6DCI Titanium in April 2011 and since its first service in December 2011 I have had acceleration problems. The main issue is when I am accelerating, when there is a flat spot with...
I have a Jaguar XF 2.7D. I have always used Redex Fuel System Cleaner, but wonder if it is really of any use? I only drive about 5,000 miles per year and only use the car for journeys of about 5 to 7 miles...
I own 2009 Nissan Murano, purchased new, where prior to running in I averaged 24 mpg. However, now that it has covered 9000 miles my consumption has improved to 28mpg running on Shell V Power exclusively....
I took my Mazda 6 (2.0 litre petrol) in for its annual service to the local dealer recently and was advised to include a new petrol additive called TuneUp at a cost of about £15 (when VAT is included)....
I have usually used only BP Ultimate diesel in my Land Cruiser, but I have recently tried the Shell V-Power diesel. I am not totally sure but I appear to be getting a couple of miles per gallon extra with...
I have now run a Chevrolet Cruze diesel auto for over one year. Since Shell introduced "Fuel saver" diesel, my consumption has increased to 27.86 mpg average over the past 1,138 miles i.e. five tankfuls,...
On 2 December 2010 I bought a diesel MINI Countryman ALL4. This is the first diesel-engined car I have ever bought. I am delighted with it as a car. It is comfortable and the performance is lively and...
I have used Shell and BP petrol and diesel fuels for their higher detergent and lubricity respectively. Other than more power, what advantages do V Power/Ultimate offer to justify the higher price, compared...
Anybody else suffer flat spots at low revs in the Ford Focus 1.8 TDCI or find it easy to stall at low revs in first and second gear?