Stick a fork in her, she is done.  Sounds like the motor is so worn out that
the gas is getting past the rings into the motor.  Oil coming out the exhaust
pipe is also an indication that the rings have toasted as gas is getting into
the oil and oil is leaving the motor via the exhaust system.  Time to save up
your pennies for that V6 Chevy engine conversion that you always wanted to
do.
Ken Wilford
John 3:16