Boys I have heard those clicks in a friend's Turbo.......my self as a technical person and as you all are driving since ages..........please note that...
IT IS NOT A KNOCKING SOUND........I AGAIN REPEAT IT IS NOT A KNOCKING SOUND........
sari zindagi ho gai gari chalatay hoy......knocking ki sound different hoti hai and you all are 100% familier with it.
it felt exactly like e.g. an ABS function of locking / anti-locking when brakes pressed hard you hear ABS.....clunking...(Krak,,,Krak....Krak) which is felt in your foot while the brakes are full depressed in emergency (The weird sound from ABS module which is normal and nothing to worried about)
Similarly,
while giving a hard throttle or pressing accelerator paddle suddenly more than half way with a mixed or regular petrol, it clicks...(Krik.....Krik......Krik) 3 times and is clearly felt in your accelerator paddle. its seems to be VSA malfunctioning / anomaly or an electronic waste-gate valve suddenly opening as these clicks....3 in numbers comes 3 times......No HOBC nothing (the car was on a previous mix fuel from total) I gave it hard short runs in S mode from stand still by touching frequently at 150km/hr, 2 to 3 times.....then in smooth driving condition tried to create a position in which it clicks..... it never happened again till now............
Now technically all Turbo Charged engines whether Generator engines or automobile dynamic engines are equipped with electronic waste-gate control valves & bypass control valves for precise control of boost pressure..I think it is an actual safety feature on an inferior petrol due to knock detonation detection by knock sensor, the turbo charger surging is diffused by waste-gate valve and what we hear is spring loaded actuator butterfly opening closing / slapping abruptly in the form of metallic clicking or clunking which ever you say..............The Waste-gate control valve is basically Turbocharger safety to save the Turbo charger from the reverse surge due to sudden load change or knocking on an engine in order to avoid damage.......
The reason of Turbo surge can be misfiring, detonation, pre-ignition, faulty s.plugs, faulty IG coils etc.......what i feel is in our case as every Turbo is new and Owners are using premium fuel or a mix of premium & regular fuel....so it should not happen....as i heard that a kind of module will be going to replace under warranty.....most probably it could be a waste gate actuator........or rather they will retard the ignition timing in order to reduce or minimize Turbo surge due to knock detonation as a result of which waste-gate valve operates......but rest assure it is not knocking but yes a metallic slapping sound of spring loaded butterfly valve of waste-gate and in turn accelerator or throttle butterfly limiting mechanism which we felt on the paddle also just like an ABS system..........
