Originally Posted by dhc905
Question - is it normal in a fully functioning e90 to have the heater on high and the tempreture change (drop) every so often? Is this a potential indication of a bad pump?
Drop as in the temperature gets colder? Or the with the fan on high, it sounds like the fan goes out for a moment and then comes back on? If its a temperature drop, it is most likely the t-stat acting up.