I think the stages are caused by the springs on the throttle body (butterfly valves) vs. the pedal itself. I popped the cover off the throttle cable attachment and moved the valve by hand. There definitely is two levels of resistance and you can even see one spring twist, followed by the second one as you open the throttle more.
Also, if I remember correctly, aren't there two butterfly valves in the throttle body? Maybe the first part of the resistance opens one, then the second part opens the other? Someone take their intake boot off and play around with it. My guess is the auto vs. manual cars the same. |