There is a transmission delay in my automatic 2010 Cooper S. It takes a while for the gears to shift from 1-3 during acceleration. It also creates a whining sound during acceleration, sometimes jerky and shuddering in slow speed as well when you step on the gas pedal slightly.. The MPG dramatically decreased.

Last month, I changed the spark plugs, coolant, battery, alignment, upstream o2 sensor, and engine oil.

No engine light.

I am going to bring it to the shop soon but in the meantime, can someone here help?

 

 

How many miles?
You have Torque connected, any codes read?
Any signs of leaking ATF? Have you checked level and condition? I'm going by the Bentley manual as I have a manual, the procedure looks like a pain.

 

41k. I think theres a slight leak only because the bottom pan is slightly wet.

 

41K seems awfully early to be having problems, even if the car is 7-8 years old.

Again, any codes?
Do you have the shift paddles on the steering wheel, and if so, does the shifting behave any differently when you use them?

 

I still have the whining sound when I manual shift. I will try to get a video and upload it on youtube tomorrow.

and no codes so far...

 

bumpppppp

 

The reader did not detect any codes or see any faults at the shop.

There is a fuel pump sound below the vehicle. When I touch this tube, it has a tapping feel.. I'm not sure if that is normal...