try this way to solve your first problem:"If the sports light flashes (indicating a possible transmission problem), simply disconnect the battery terminals for approximately 10 minutes. This action will reboot all the onboard computers and usually solves the problem. " . you can also reference this link: http://www.epinions.com/content_24668900996
my car is Honda Accord 91. It had the same faults with yours. The speed meter and mileage meter didn't work. When you drove, the "S" signal light always flashed. I went to a garage, they changed a sensor for my car. Now, everything is ok. I have tried it on highway. The cost is $170.
Good luck, everyone!