Hello guys,

My 4.4i X5 has number of things to have replaced. Thermostat, 2 O2 sensors(One front on bank 1, and One rear on bank 2) and a Mass Air flow sensor. I have bought a New Thermostat and going to buy a new MAFS. as for O2 sensors, there is only one Dealership in my city/countrey. and they don't have them in stock. My mechanic told me that I can buy used one as far as it's good. I have found both of them for 60$ with the warranty that they are working. I need your advice... should I buy used once? or wait for them 2 weeks? and also if it is reccomended to change all them at a time.

Nick