I have a 98 Malibu 3.1 keeps setting P1665 and the check engine light. Also noticed last couple of weeks it doesn't like to take gas upon fillup, have to run the nozzle real slow. Vent solenoid ? Also getting intermitten P0137 low voltage o2 sensor bank 1 sensor 2. Would that be post converter ? Haven't crawled under yet to see how many it has. Thanks in advance for the help.