My 1996 Volvo 850 wagon / non turbo with 223K miles on it starts runs rough and stalls. First i had a bad ECT i replaced that and drove it for 6 months with no problems. I let the car sit for 14 days to return to a car that ran real rough with no codes being returned. I turned up the car plus,cap,rotor,fuel filter with no change. I then changed the MAF cleaned the injectors and tested relubed the o rings and re installed. Then i test drove the car with hesitation and stalling when attempting to idle then i noticed smoke coming from underneath the vehicle to find the cat glowing cherry red. I then replaced the cat with no change except when the car stalls i have a return code of P0410 Secondary air injection system. I also tested the fuel pressure at the inlet line feeding the fuel bar it is a steading 40 PSI while cranking and when taking the reading at the end of the fuel bar while it is running the pressure is @ 43 PSI. Can anyone help? PLEASE PLEASE Thanks The D.I. Man [/align]

 

Sounds like you might still have a bad MAF or a really big vaccum leak.