pontiac bonneville3.8 with 5 codes p0141 p0300. p1404. p0440. whats causing these codes.

Question

The car is stalling and the

Answer 1

P0141 02 sensor heater circuit malfunction (Bank 1 Sensor 2)

P0300 Random misfire

P1404 EGR closed position malfunction

P0440 Evaporative emission control system malfunction

When the EGR valve get stuck in the open position you can expect a misfire condition with a rough idle.and stalling at a stop or at a idle, replace the EGR should solve the P0300 it may be the cause of P0141. As for P0440 right nect to the EGR valve is the purge solenoid, , there is a vacuum hose that tends to rot away, replace that hose ,