Manual gearbox, engine torque limitation

WARNING: This page is about a different car, the 2001 Saab 9-3. However, it is still accessible from the selected car via links, so may be relevant.

Fig 1: Manual Gearbox, Engine Torque Limitation Graph

Courtesy of SAAB-SCANIA OF AMERICA, INC.

The maximum engine torque must be limited at low gear ratios for reasons of strength.

The control module calculates the engaged gear by comparing engine speed with vehicle speed.

If the gear ratio corresponds with gear 1 or R, the control module reads bus information "Reverse gear selected" from DICE to distinguish between them.

The engine torque (for the B235R) is limited to 250 N.m (230 N.m for the convertible) when 1st gear is engaged. Torque limitation in reverse gear R is 230 N.m. In 2nd gear, the torque is limited to 330 N.m (315 N.m for the convertible). Other gears are limited to 350 N.m. The torque is converted to mg air/combustion and constitutes the maximum value for the air mass/combustion allowed by the gearbox. Refer to the table below for corresponding torque limitation values for the B205E, L and R.