Ask Honest John

Most recently answered turbo engines questions
Thank you for recommending the Mondeo 1.6 EcoBoost. Your review advises "1.6 EcoBoosts need idling from hot before switching off otherwise oil in the turbo bearing and oil feed to the bearing can carbonise....
I have queries on two issues on which you have advised several times. Firstly you have warned that a turbocharged engine should be left idling before switching off to enable the turbo bearings to cool....
I have just bought a 2011 Mercedes C-class Blue Efficiency, with a petrol engine. Do I need to take special care before switching off the engine, because of the turbo?
Can we have redress with Ford after turbo failure at 65,000-miles for a 2007 C-Max? They have not told us why it has failed or given a sufficient explanation.
I have just bought a very low mileage and immaculate 1990 Lancia Delta HF Turbo. Do you have any advice about looking after the turbo? It makes a ‘whoosh’ sound when coming on. Is this normal?
We own a 2004 Renault Scenic. We have had it for under a year and already spent quite a bit on it. We had a engine rebuild at the end of last year trying to find a fault which cost £900, bought two new...
The 'start-stop' system on my new Volkswagen Golf TSI is operating very smoothly and presumably contributing to its relatively good urban fuel consumption. However, I recall some discussion about the risk...
I have a 2007 Ford Focus. The car suffered with injector problems and I fitted a new turbo and all the trimmings as advised by my local mechanic, but now, after three days, I am getting system faults and...
I read with interest your replies about the diesel/petrol question and your recommendation of the Ford EcoBoost engines. I find the idea of these very attractive, especially the 1.0 EcoBoost in the Ford...
The 'start/stop' system on my new Volkswagen Golf TSI is operating very smoothly and presumably contributing to its relatively good urban fuel consumption. However, I recall some discussion about the risk...