Whilst driving on the motorway at 70 my car seemed to misfire and loose total power so i pulled over to the hard shoulder and even when revving the car in neutral there was no power it was almost like a limp mode. i switched the engine off and waited 5 mins and the car was back to normal for about 5 mins and then it happened again. so i got the car home and scanned it with VAGCOM and a whole host of errors: 6 Faults Found 18104 - Powertrain Data Bus: Implausible Message from Steering Column Controller P1696 - 002 - Lower Limit Exceeded - Intermittent 16395 - Bank 1: Camshaft A (Intake): Retard Setpoint not Reached (Over-Advanced) P0011 - 008 - Implausible Signal - Intermittent 16814 - Catalyst System; Bank 2: Efficiency Below Threshold P0430 - 002 - Lower Limit Exceeded - Intermittent 17443 - Sensor for NOx (G295): Signal Implausible P1035 - 008 - Implausible Signal 16575 - Fuel Pressure Sensor (G247): Implausible Signal P0191 - 002 - Lower Limit Exceeded - Intermittent 18974 - Low Pressure Fuel Sensor (G410): Short to Plus P2542 - 001 - Upper Limit Exceeded - Intermittent Readiness: 0000 0000 I have cleared these errors and the car seems to be ok but there is now one error which won't go off which is: 1 Fault Found 17439 - Intake Manifold Tuning Valve (N316): Setpoint Not Reached P1031 - 004 - No Signal/Communication - Intermittent Readiness: 1110 0101 so i have now opened my intake manifold and its pictured below: it doesn't look like its closing properly but its not seized i have cleaned it up and replaced it for now. would this have caused the problem? i also took out my spark plugs and they looked like this: Would it be safe to say that i need a new intake manifold flap motor? i have also noticed that when i rev the car while driving or in neutral i get a sort of zzzzzz noise i noticed this noise also when i was on the motorway. it gets louder web i accelerate or rev the engine.. Please can anyone advise?