Ask Honest John

Most recently answered dpf questions
Are DPFs a legal requirement? What do you think of ECU-Flash's DPF removal service, please?
Whether dealers try to force regeneration of DPFs or Eolys fluid top-ups, at some stage the DPF will need either replacing or cleaning because of a build-up of ash inside. With trucks, we find it's between...
I purchased my Fiat 500 diesel Multijet in April this year. It's about five years old. According to the service history, the oil was changed in October last year. The flashing oil light came on in May,...
I have driven a Saab 9-5 Vector Estate 2.3t from new since 2002. I love the car and have put off changing it because I cannot replace it with another. What do I replace it with? Mercedes-Benz, BMW or Audi?...
I'm considering buying a Mazda CX-5, which I’ll drive for 8000 miles per year. You say the diesels should not be subjected to short runs if at all possible, but what is a short run? My pattern of motoring...
I am considering the purchase of a secondhand Jaguar XF or XJ about 3-4 years old, but from reading your various concerns about particulate filters, I am also concerned. My annual mileage is no more than...
I am thinking of buying a 2012 KIA Cee'd 1, 1.6 diesel manual. My mileage is approx 8000 - 10,000 miles per year, roughly 50/50 short journeys and motorway. I have been told if once a week I do 50-60 mph...
I purchased a brand new Vauxhall Corsa 1.3CDTi on 07-09-2012. Since then it has been back in the garage five times due to DPF related problems. It has currently been in the garage for eight weeks waiting...
My Vauxhall Combo van is suffering from a loss of power and black smoke. The engine light is also on and no garages can solve the problem. I have a suspicion that the DPF is not doing what it should, can...
A family member is selling their 2005 Volkswagen Polo 1.4 diesel. It has only covered 36,000 miles and has a full service history. I think it will be offered for around £3500 - is this a fair price?