slowpoky

Hi,

​​​​​​I recently bought an Audi A6 3.0 TFSI 2015 with 70.000km.
​​​​​​After couple weeks of driving I had a major problem: after pushing the throttle and lifting immediately after, the engine stuttered and I noticed a rattling sound. (At 40km/h approximately 1500-1800RPM.)
Workshop concluded the engine had piston damage, bearings were damaged and a complete engine swap was done. No error codes showed up.

I did some research and found out the previous owner filled it up with Diesel and drove a couple km's. Car was towed to Audi and they swapped fuel tank, pump and fuel lines + spark plugs And oil. No injectors were replaced. Car was sold shortly after(ofcourse)..
Couple weeks later, complete new engine: same problem reoccurred.. throttle lift after acceleration (so it will upshift) and again engine stuttered a brief moment. EPC light went on: P0090 Fuel pressure solenoid up turns out. Luckily I heard no rattling noises this time and engine is running oké.
oké. Could someone clarify what could cause this issue and would it be possible the new engine also has been damaged due to high fuel pressure?

​Thanks in advance!

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