Honest John Technical Q&A Part 12

Nov 18, 2019

Honest John Technical Q&A Part 12

Q) All modern diesels have DPF problems if used for short journeys but are some makes worse than others?

A) Yes. Best where the engine has an integrated exhaust manifold and the DPF is located immediately next to the engine.

Q) What's better - winter tyres or all-weather tyres? I have purchased a 2019 Suzuki Vitara 1.4 Boosterjet. As I live quite high up, the roads in winter get very icy. Would I be better buying winter tyres or all-weather tyres?

A) If you are prepared to swap tyres every November and every March, then high quality cold weather specific tyres will be best. But the latest all weather tyres such as Continental AllSeason Contacts are so good that there is no real need to go through the fuss of swapping tyres over twice a year.

Q) I have just found oil in my radiator and expansion tank. Any thoughts/suggestions as to what this could be?

A) We would suggest that the cylinder head gasket has failed. Does the engine start okay and run okay with no misfire? You may be best at this stage to have a compression test carried out as this will confirm the head gasket situation.

Q) Yesterday at its first MoT, my BMW M240i received an 'advisory' for cracking to all four tyres. Is this unusual and should I be concerned?

A) Tyre cracking is quite common and usually caused by UV light drying out the chemicals within the tyre. Obviously, if the MoT tester has given an advisory, the damage is deemed to be significant. And given that your car is fairly powerful (and has the potential to put a lot of stress on the tyres) we'd recommend replacing them.

Share this post

Car Service

Car Service

Need a basic, interim or full service? Compare quotes.

Get Quotes