I have a 2000 Contour with the V6. It will run fine for a day or two and then just start sputtering, missing and sometimes dying and it takes in 5 minutes to 4 hours to restart. Took it in to a mechanic and he said the intake manifold gasket was bad, had it replaced and the temperature sensor for $450 and that didn't seem to help a bit. Today, driving along on the interstate, the thing started bogging down, missing, CEL starts flashing, and finally died, died 2 more times in the 4 miles home, and the last time took about an hour before it would start again though the CEL didn't start flashing again. Running fine now but will start again any time I drive it. It seems worse at 1/2 tank of gas or less but can't be certain. The mechanic now says it needs spark plug wires for another $200 though another mechanic friend looked and said they are fine. I think this guy has ripped me off and is just guessing now. Drove the car by his place with the codes in hand (after I stopped at Advance Auto to get a read) and he says "you can't trust those codes to tell you what is wrong". Also, over the last few months this thing has been getting worse. Last fall it only did it on hot days but now any time (though warm days seem to be worse). Below are the codes that I got today after today's incident when I took it by advance auto parts. One other thing, after I bought the car, I noticed a slip of paper slipped into the owner's manual that had written on it "fuel rail problem". Any thoughts on what the problem is or what I can do as right now I'm not taking it back to the mechanic as he is just pulling ideas out of body orifices...I mean really, spark plugs and/or wires don't have these symptoms. HELP!!!!

p0420 - Catalyst efficiency below threshold (bank 1)
p0430 - Catalyst effiecieny below threshold (bank 2)
p0190 - Fuel rail pressure sensor malfunction
p0301 - Cylinder 1 misfire detected

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