Ask Honest John

Most recently answered diagnostics questions
I have been having problems for the last four months with misfiring, i have replaced both harness's the ecu and four injectors. Every time a part is replaced it goes ok again for a bit then it starts misfiring. If...
I run a Vauxhall Corsa diesel 1.3 Club, 58 plate, 43,000 miles on the clock, regularly serviced. It is a driving school car. Recently, in the middle of the day, the engine suddenly faded and cut out...
Took delivery of my Jaguar XF 2.2 on 7/01/2013 5mls on the clock. NO heat coming into car.Dealer took it in NO faults registered on computers or shown on PDI. Dealer is stumped. put call into Jaguar before...
I have an engine system warning light come on in my 55-plate Focus TDCi (red cog like with exclamation mark in centre) any ideas please? Car has done just over 93,000 miles and was going to get belts change...
I was just seeing if you know where the socket is on a Volkswagen Lupo 1.0 petrol so I can chip the car to give a bit more power? I have the kit for it but just can't find the socket to do this.
My car, a Mazda 6 TS2 Diesel 2.2, is kept in the Alps during the winter at a height of 1300 meters. In February for two weeks, the temperatures ranged between -19c and -10c. The first part of any journey...
I have a 2009 Mercedes-Benz C220 CDI. Over the last week a single bleep has started emit from the centre console area every four to five minutes. This happens both with the radio/CD player on and off....
My car is a Golf GT Sport TDI and it is three and a half years old. The ABS light came on and I took it to my garage which did the diagnostics tests. £170 later I was told it was the ABS controller unit....
Hello, do you recommend any particular OBD kits? What kind of OBD would suit my 2006 Ford Focus 1.6TDCI?
We had problems with car running on a short distance with flooding and drys up and restarts. The AA have been out on occasion, and after first diagnosis pointed to throttle body housing and lamba sensor....