Question! If you fuel your 1.4 TSI engine with 98 instead of the recommended 95, would you actually gain performance or just lose money since it isn’t specifically tuned for 98?

4 Comments

1. 

   bonerlad 2 years ago

   Everything I’ve ever seen test this has shown a power increase of less than 5hp and any fuel economy gains too small to even start to recover the cost of the more expensive fuel.

2. 

   ExChange97 2 years ago

   There is a point if compression ratio allows it. And fuel quality itself, at some places “95” can actually be lower octane so with 98 you can be a bit more confident. Would i do this on low power engine? Probably not unless i chip it. Im not an expert, correct me if im wrong

3. 

   HeisseGummiente 2 years ago

   Driving a 1,4 TFSI here.
   In the fuelling flap it says 95 or 98.

   I got the feeling that with the 95 it simply runs smoother … so that’s my standard. However the 98 works too but especially in summer (hot summer day), the engine might run unsmooth when for ex. waiting at a traffic stop and waiting (800-1000 rpm of the engine).

4. 

   jcforbes 2 years ago

   To really honestly answer this question you’d have to take some data logs and see if it’s pulling timing at all on 95.

   I’d venture to guess that 95 is sufficient.