The governor valve is sticking, possibly due to varnish buildup in its bore. As the car speeds up, centrifugal force causes the spinning valve to move against spring pressure. As you slow down, the valve moves back due to the spring. That valve, along with the throttle position, determines shift points.
When the governor valve sticks, the transmission thinks the car is still moving fast enough to warrant staying in second gear.
There are cleaning chemicals that may help dissolve the varnish. Some cleaners must be removed by flushing and replacing the transmission fluid. There are other additives that can stay in the fluid. Ask the folks at your local parts store what they recommend for your symptom.
Wednesday, December 9th, 2009 AT 12:48 AM