Hey everyone, I am new to this forum and have a 2009 mini hardtop. It has 40k miles and recently I have noticed it becoming sluggish when i drive, and my gas mileage has gone down to high 20's. What could this be from, I have not taken it in since my warranty went out at around 36K. I am not car savvy and don't know what it could be. Thanks.

 

Could be carbon build up on the back of intake valves. These have direct injection engines which increases power and efficiency.

Check warranty again - believe warranty is 50k miles or 4 years. The free maintenance (free oil changes, free brakes replacements) is 3 years or 36k miles. You should still have warranty coverage.

Good luck.

 

https://www.northamericanmotoring.co...-build-up.html

 

You had a 36K Maintenance Plan which covered wear items like brakes, windshield wipers, bulbs etc but that is in Addition to the Standard Warranty which is really 50K miles or 4 years which ever comes first.

So in reality if your car is a 2009 and only has 40K on it you are still have "Warranty" left.

One person mentioned carbon build up but that is only if you have a S model. Can you tell us a little more about your car as you only mention that it is a hardtop but to help you we need to know is it an S or Non-S as they are slightly different engines and they way they work and what can cause the problems you are describing could be different.

 

I have a non S model. I have no performance modifications done to it.

 

Well theres why it feels sluggish! haha jk.

Maybe a vacuum leak. Do you hear misfiring/knocking?