I have a 92 Grand AM with a 3.3l engine and I guess a TH125c transmission. I can drive the car sometimes quite a while and all of a sudden the torque converter locks up eveytime I stop. I was told it may be the TCC switch. How can I get my hands on something that will assist me on changing this switch? Seems like the little autozone repair guides don't cover this switch in great detail. Is there like an additive that might make this switch work better?