1995 toyota corolla dx 1.8 auto 4 speed code 42 most common fix other than speed sensor?

Question

Code 42!Replaced the speed sensor with 3 new ones. tps is ok tried new 1 too. tried speedo head no difference. tried ecm worked good for 1 mile then trans downshifting again on accel. and speedo drops off till you let off gas. car is crazy any help please losing my mind!

Answer 1

you may a short in the wiring, or bad ground.