TCC solenoid shifting issues

KJSMIMI16

MEMBER
1999 PONTIAC GRAND AM
2.4L
4 CYL
2WD
AUTOMATIC
120,000 MILES

I have been having issues with my car shifting hard after it has been running a while then stalling on me almost causing a huge accident that could have been a tragedy. My husband hooked his code scanner to it and came up the TCC solenoid so he replaced it and now the car is shifting but it is delayed and it is like you are pushing the accelerator but not getting anywhere. Please help me figure this out.

1 Reply

JACOBANDNICKOLAS

MECHANIC
108,320 POSTS

Hi and thanks for using catalytic converter

The computers need relearned to make the shifts correct again. It requires a live data scanner. I have basically cut and pasted information related to this. According to the repair manual, when the TCC is replaced, this needs done.

The transmission adaptive pressure (TAP) information must be reset. Resetting the TAP values using a scan tool will erase all learned values in all cells. As a result, the ECM, PCM or TCM will need to relearn TAP values. Transmission performance may be affected as new TAP values are learned.

Here are the directions and a better explanation.

The PCM maintains the Up-shift Adapt parameters for the transmission The PCM monitors the A/T ISS sensor and the A/T OSS during commanded shifts in order to determine if a shift is occurring too fast or too slow. The PCM adjusts the signal from the transmission pressure control solenoid in order to maintain a set shift feel. Transmission adapts must be reset whenever the transmission is overhauled or replaced. In order to reset transmission adapts, select the following:
1. Tech 2
2. Special Functions
3. Transmission Output Controls
4. Clear TAPS

I hope this is helpful. Feel free to ask other questions if you have them.

Take care,
Joe