The problem with the gearbox on my Rav has come back and I noted P0755 again (using an OBD tester I bought form ebay), from 1st to 2nd gear the revs go up and 2nd takes a while to kick in. From standstill going into R and D are jerky. Before I send the ecu back for a retest, I will have the gearbox oil chnaged and the Solenoids checked/replaced. The O2 Sensor issues are always there, obviously the engine light goes away when I reset, if the gearbox issue is fixed I will invest and have the O2 sensors changed and keep the Rav for another 2 yrs. Not sure but if you keep driving with those faulty O2 sensors you might damage your cat what cost way more then those £105 plus sensors if bought at http://www.ecolambda.co.uk/