I have a 94 Bonneville with the plain 3.8. It acts like it wants to stay in high gear or something after you get going. It will not kick down like it should if I was to try and pass sometime. It just gradually picks up speed. Advance checked it and said it was the throttle position sensor. Well I changed it and the check engine light still was on when I started it. Took it to Advance and they tried to clear the codes and everytime it did it would kick right back on. So he checked it again and it said throttle position sensor signal was low. What are the chances that the new sensor is bad? I was told not to unhook the battery when installing it but I did. It said to right on the box. Please someone reply if you have any ideas on my problem.

Have a 95 bonneville doing the same thing only I didn't notice it. Mechanic brought it to my attention, by checking codes. He clean MAP sensor along with replacing the PRNDL switch (shift control, THE Park, Reverse, Neutral, Drive, low) switch. I notice an improvememt right away, just like when it was new. I don't know if cleaning MAP SENSOR and/or replacing the switch solve togehther solve the problem.

Hope this helps

Im thinking it could be a vaccuum leak or some valve that senses you have punched the throttle and want more power. I forget what it is but its something to do with the vaccuum.
I realize the TPS is throwing a code though and Im not sure if the PCM is guessing but we all know it does at times.



Good luck.

Mine is not super charged. So where is this vss sensor?

Vss sensor is passenger side low back of engine. Not sure if the sensor runs a independent line to the PCS and a cable to the speedometer like Ford. But if dont then your Speedometer would show something.

IF the VSS is irratic you would have a transmission doing funny stuff I would think.

Good LUck.