I'm noticing the "S" light indicator going on and off erratically (not
steadily) at times on my 91 Accord (automatic transmission). Usually
it will go on in the beginning of a trip and then usually go out and
stay out for the remainder of a short trip. I did notice it shift
differently when the light was on as opposed to off today. Also I've
been noticing a slightly louder engine rpm's than normal for weeks
thinking it was an exhaust leak till now. Assuming this all is a
transmission problem, who is best to diagnose this (Honda dealer
service dept as opposed to others). I'm not sure I can replicate the
problem ( "S" light indicator) on cue for any shop when needed to.

Any idea what transmission work costs today??

Any ideas how best to approach this? I don't want to ignor it.