Ok, another reason not to go to the dealer: Last time I was in, they changed the oil and replaced a brake light harness, then only filled the tires to 25psi, where the max pressure for my tires is 50 psi!
After correcting this today, the TOD lights remain stable, the engine doesn't jump between gears, runs smoothely. Back to normal! Never knew tire pressure would cause the TOD to be so out of whack, but thanks to another post on this board, I put the pieces of the puzzle together and decided to fix the tire pressure. Thanks Vehiboard! :-)