My Mercedes-Benz SLK has had various faults recently - should I extend the warranty?

I have a four year old Mercedes-Benz SLK with 19,700 miles on the clock. I've owned it for a year and it has been covered by a warranty, which has now just expired. So far, it has had a new RPM sensor,...

Are the known tyre sensor faults on my Renault Clio grounds for it to be replaced?

I have a 2015 Renault Clio with approx 18 months warranty remaining. I've had persistent trouble with the tyre sensors malfunctioning and have had three new tyres already. The dealer says it's a fault...

Problem addressed in warranty that continues after warranty period - what can I do?

My recently purchased BMW (08) has developed an engine sensor and injector fault. Dealer has approved repair, but should other items such as coil also be fitted? If they are not, and the fault happens...