So I picked up a 2001 Bonneville with what felt like a misfire. Scanned it, no codes. Swapped out coil modules, plugs, wires, no change. So I thin noticed when it was cold it did not do it and then realized the TCC does not enable until warmed up. I then test drove and if I lightly pressed the brake to disengage TCC it would stop the fishbitting instant so I knew it was TCC related and only happened when TC locked. So I did some massive Google searching. Found people were cutting the brown with ont eh trans plug to disable the TCC permanent. Also found guys who would cut the wire but wire a switch into cabin to turn it off/ return to stock. I did this, worked great. I then read more deeply that the TCC lockup signal is a PWM modulation of supplying a ground to one side of the TCC solenoid. I decided to test a full ground for a short period so it did not burn the solenoid out. It would perfect. TCC would lock and no fishbite with full ground. So I then tested with a 2.7 ohm resister in series and it worked. With an 8 ohm the fishbite returned. So I am wondering is the TCC solenoid is wore and wont hold the TC locked at the rate of the ECU PWM signal.
So, I have a few questions.
1. Could the ECU PWM signal be modified to supply a more “complete” ground?
2. Is what I read that the PWM signal is to smooth in the TCC lock and never really supplies a full ground?
3. When I switch in the ground with the 2.7ohms is much smoother that pure ground. Pure ground was a harsh engage. Any tips/ ideas further I should try?
4. Would an ECU swap be worth trying to see if the PWM TCC engage would be more sure?
