This is a series of symptoms.

Day 1 the engine trembled when I press the gas (accellerator) to 3K rpms and
above while car was parked (did both neutral and parking gears). I drove it
that day for about 10 miles.
Day 2 the engine simply started but kept trembling (even whout pressing the
gas), then died after about 2 minutes. I tried about 3 times to start it
again, but it did not start. I could hear the starter motor sound. So I left
it on my driveway and went out. A few hours later, I was able to start it
and drove it into my garage. It showed "Service engine soon".

Anyone any idea on what went wrong and what should I do to fix it ? the car
has 60k milleage.

Many thanks,
Xinghong