ECT stands for Electronically Controlled Transmission, and is a feature attached to the automatic transmissions of some older vehicles.
In cars without electronically controlled transmission switches, the gear is determined by a combination of the engine RPM and speed of the vehicle. Generally, the automatic transmission will shift into a higher gear soon after the engine exceeds 3,000 RPM. This is to optimize fuel economy.
But, as all drivers know, certain situations call for a higher torque output that can only be achieved at higher RPM’s. For instance, quick acceleration is not going to be available at 2,500 RPM, so sports drivers usually keep their RPM’s much, much closer to redlining than the manufacturer would like.
Besides sports driving, a suitable time to engage ECT Power is when you are driving over mountain passes and the additional torque generated by higher RPM’s is needed to maintain speed while climbing steep inclines.
This last weekend I took the family to Hiroshima (home of Mazda and the Mazda Automotive Museum) for a mini-vacation. The mountains between Osaka and Hiroshima are fairly steep, and my Hilux Surf would ascend the inclines at first, but as soon as the the speed exceeded, say, 120 km/h, the automatic transmission would shift into a higher gear; the engine RPM thus decreased and we were left torque-less and this would cause a loss of speed on the inclines.
So I engaged ECT Power. What difference! After engaging ECT Power, I was easily able to maintain a constant climb speed without having to floor the accelerator to force it into a lower gear.
Some vehicles equipped with ECT Power switches are (some models): Toyota Hilux Surf also known as 4Runner; Isuzu Wizard (Rodeo); Toyota Tacoma; Toyota Avalon; Nissan Pathfinder; and the Lexus IS200.
Warning: Engaging ECT Power full time will dramatically decrease your fuel economy.