i have an ex police octavia estate 2008 4x4 6 speed, all has been great  until recently whe i started to get a wump wump noise from engine, no warning light, no overheating no luss of power just this awful noise when on tickover and becomes more metalic when driving.

put myVgate scan machine on it and it came up with the code for heater plug 3, so i have changed heater plugs, ..still the same. i have cleaned the egr valve and hoses, the mas valve , cleaned turbo checked for leaks....nothing the noise sounds expensive.any ideas please

it has done 196000.00 miles plus all the tickover standing still hous when in police :-)

re the above, when you touch the hoses from the egr and turbo you can feel the pulsating  in them if that helps