[Smith1000]

You have done some great research. I did this years ago and still use a toggle switch to throw out the tcc in my '97 Lesabre, when the car has the fishbite. It usually happens during fairly warm weather. From what I recall, it requires 12 volts to disengage the tcc, or to lock it out. I cut the brown/blk wire on the tranaxle. Leaning into the car looking down (facing the car from the front), it is the top wire on the right coming out of the transaxle wiring harness. I added wire and looped through the cab to a toggle switch. The wire loops back out and reconnects to the other end of the cut wire. I ran a 12v source to the "on" position on the toggle switch. The wire simply loop through the cab switch, but when it "bites", flip the switch on and it feeds 12V to the tcc, which holds it in the disengaged position. I found a 12v source in the cab (under the dash). It will smooth out and the RPMs will increase slightly. The check engine light will come on. The CEL will clear the third start up after, if the toggle switch is put back in the off position. After flipping the switch to on, I usually just wait until the CEL comes on (it will when the tcc tries to engage at about 40 mph) and then flip the switch to "off". Once the code is set, the tcc will not again attempt to engage until the next start up (kind of a reset for the next start up).

I have put approximately 135-140,000 miles on the car using the switch. The car now has about 210,000 miles on it and it still runs great. I try to use the switch conservatively. During the winter, I never have the fishbite issue because the tranny doesn't get hot enough.

I haven't really noticed any drop in mileage with the tcc locked out. The increase in RPMs is only slight. It probably does use somewhat more gas when locked out.

The tcc does have 12v with the key in the on position. It does not lock in (no power to tcc) until the car reaches about 40 mph. When it gets up to speed, the power is shut off to the tcc and it engages, or locks in. It takes 12 volts to disengage the switch and hold it disengaged.

I found the wire by running a straight pin through each wire on the tcc (test each wire separately). Ran a wire into the cab to a 12v test bulb. Initially, the light was on. I started driving. When the tcc locked in at about 40 mph, the light went off and the fishbite started. If I applied a constant source of power to the wire, the tcc did not lock in and the fishbite never occurred. It turned out to be a fairly simple solution. From what I read, a correct fix would be to pull the transmission and replace the valve body. This would involve a complete rebuild, which would have run about $2,000 several years ago. The valve body seals get hot and fluid slips past causing the fishbite, or slip, when the tcc is engaged. The result is fishbite. Let me know if you need any further information on it.