Was driving home from work in wifes 01 sebring and it died at a stop lite. it started back up but check engine lite is on. took off and as soon as it hit 3k rpm it started bucking {missing} like it hit the rev limiter. Made it home and turned it off and started it back up. It will now rev past 3k but engine lite is still on. its a 2.7 v6 with 104k on it I've always used synthetic oil in it do to the feared "sludge" problem. The temp and oil pressure are normal. Just wondering if a sensor just failed with no warning or if there may be a more serious problem.