Hi Members!

First Post Here. I would be grateful for any help or insight the group may provide in troubleshooting my sport mode issue. My car is equipped with the 4 speed Hydramatic 4L80E automatic transmission. In theory the sport mode switch electronically controls the transmission control module (TCM) to control shift points, torque converter clutch apply and release, and line pressure. In normal mode the car is designed to start off in second gear unless the accelerator is depressed to the kick down position. Sport mode is supposed to allow the engines power to be utilized to its full potential at all times (higher shift points) as well as enabling start-offs to occur in first gear. My problem occurs when I enable the sport mode switch nothing seemingly changes functionally from normal mode program. The sport mode indicator on my dash lights up but does not result in the activation of the sport mode operating strategy. In the past, I had an XJ6 where you could discern distinct and notable difference in performance when utilizing the sport mode selection.

The car only has 43K miles and is pristine. Aside from the aforementioned the transmission functions flawlessly.

Thanks in advance for any responses which may show me the way.

I am curious if I unplug the battery for a while might it reset my TCM?

K