have a 57 plate a3 2.0 tfsi showing 39,000 just driving home tonight doing 40mph slowed down for roundabout as got round it and pushed the pedal the car started juddering and my engine management light was flashing, pulled over right away and 1st thing i noticed is that the revs were bouncing up and down just above and below 1,000 rpm. was 2 miles away from home so drove it back and noticed a power loss and felt like car was spluttering. plugged my machine in and it came up with these codes, 00768- rear heater core temp sensor (g154) 00772 - 0.3 bar oil pressure switch (f22) has anybody have these codes come up before, and what it is thats throwing them up, only had the car a few weeks. well pi**ed off. does anyody know what could cause this and will it cost me lots of money just after christmas too. all help is really appreciated as i need it fixing asap as its my only means of transport and back at work on next week.