The injector in my Mazda 3 has failed - is this due to using supermarket fuel?

Whilst driving along, my 2012 Mazda 3 1.6d (39,000 miles) suddenly juddered and went into limp mode. I cautiously negotiated to the hard shoulder with the dashboard lit up with maintenance, ABS, and warning...

Why is my car having issues since I used Redex petrol cleaner?

When I first start my 2001 Ford Mondeo in the morning it is great, however when the engine warms up I start having problems. It doesn't matter what gear I'm in, whilst trying to accelerate it jumps forward....