My 2001 Honda Accord runs great, but if the car has been sitting for more than about 6 hours the transmission slips between 1st and 2nd gear. It only does this the first and sometimes second time I accelerate, then it runs flawless and smooth. The mechanic says nothing is wrong with it, but I was wondering if anybody has had this problem and what they did to remedy it? It is a 4 speed automatic transmission. Any suggestions would help. Thanks. Oh, the car has 98,000 miles on it.