My Audi has been having trouble driving for about 6 months now because when in a idle it shakes rough at times and doesn't feel good. When I accelerate hard the car starts jolting and it just wont accelerate like it should whatsoever. THe car pulls really hard then around 3000 RPMs when I have the car close to floored it basically starts jolting really badly.

I took it to the mechanic and after o2 sensor replacements, fuel filter and after doing all this they finally figured out it was a piston seal. Meaning I need a new engine because it is supposedly leaking oil on my spark plugs. I didnt want to replace the engine just yet so I took out the spark plugs that my VAG was reading were misfiring (Cylinder 6 and 4) and they were very clean with little carbon build up they looked as they should. So I'm also getting a code reading g236 for the exhaust gas temp. Would this sensor cause the jolting the car is doing when I drive it? Do I have any options? If you have any ideas I'd appreciate the advice. Hopefully I can avoid replacing my engine.

Thanks