How to Tell the Difference Between the FSI amp; the TFSI

1. Examine the outside of the Audi for signs that the vehicle is a diesel. If the badges on the back of the car contain 'TDI' or 'Diesel,' the vehicle is not equipped with a FSI or TFSI engine. If the car is missing the badges, open the fuel filler door and look for the word 'Diesel' on the fuel cap.
2. Look for the word 'Turbo' or the letter 'T' on the back of the Audi right after the engine size designation. For instance, an Audi A4 equipped with a TFSI engine will have the following badge on the back: '1.8T.'
3. Open the car's hood and inspect the vehicle's engine cover. TFSI-equipped vehicles will have the word 'Turbo' stamped on the engine cover adjacent to or below the Audi four-ring logo. If the Audi is not a diesel and is not equipped with a turbo charger, the engine installed is the standard FSI engine.