Never ending

I had sent complaints before about issues on my car, the engine had been replaced under MotorPlan in 2013. <br> <br> Shortly after that I had still been experiencing problems with the car 2014/2015 the car is a R56 Mini cooper JCW .<br> <br> I received a quote of 13000.00 for FRM replacement as they said this was the problem. I accepted and when the work was done I was assured that the car was fine. As soon as I took the car out of the parking lot, the problem was still there (incorrect fuel level and car not performing as usual after 4000rpm).<br> <br> I drove home and two days later I had taken the car back to BMW, they told me they would call with a quote again (surprised), because they are the ones who misdiagnosed the problem on the car. Being desperate to get my car fixed I told them to get it done. Now being an air intake pipe being cracked problem it costed an additional 3000.00<br> <br> I picked the car up today 2 February 2015 and again made sure that they test drove the car and it was fine. <br> <br> Again the problem was still there. <br> <br> Please give me a proper explanation this time. Not from call centre employees. I would like some actual assistence.<br> <br> You records will show the work done on the car.