Thanks for the help
I bought the car two years ago and it is a belt driven engine. I have already changed the belt one week ago as the bmw dealer told me to do so as it should be changed every 65000 miles. This engine is mostly used in 3 series car but here in Mauritius it is very common in 5 series.
Here we have only 'Super' fuel and I have already
put an additive in the fuel with no result