Hi guys i'm new to this site and i have two questions regarding the ECU on my 95 540i production date 9/94. The first issue is that the engine is pinging with or without a performance chip installed, premium gas and octane booster in the tank, i took the car to an independant shop and they hooked it up to their computer wich detected the engine pinging but the ECU would not do anything to adjust the timming, they told me that the timming was fine and so were the knock sensors, they said that if the knock sensors were bad they would trigger a fault code, so the only thing they suggested was to replace the ECU , do you think that is the problem? And the second issue that i think may be related to the first one is when i turn the engine on first thing in the morning or whenever the engine is cold as soon as the engine fires i hear a loud high pitched metallic BINGNNN kind of the same sound a bell makes, and it only makes it for a second. What do you think that could be? Thanks a lot for the info