P0420 is a Catalytic Convertor code. If one of the oxygen sensors is causing this code is most likely the rear one. But you could have a bad catalytic convertor, an exhaust leak near the catalytic convertor, or a running condition causing this code. Just replacing one of the oxygen sensors would be a total guess.
Code p0420 is it sensor 1 or 2?
2000 Cadillac DeVille
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Maintenance & Repair
Can the sensor in the door cause the cars computer mess up?
2000 Cadillac DeVille Sedan FWD
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Maintenance & Repair
Okay, after an hour or so, I was finally at a point of pulling the fuel pump out of the gas tank and replace the fuel level sensor. BUT... the (cussing implied) fuel pump will not come out of the tank...
2002 Cadillac DeVille Sedan FWD
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Maintenance & Repair
Can the oil sensor cause problems with the computer. I have a 2000 deville base.
2000 Cadillac DeVille Sedan FWD
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Maintenance & Repair
Can somebody please tell me where the temperature sensor is located. I change the relay and check the coolant and a fuse and my fans are not kicking on still. Any helpful ideas will be greatly app...
1991 Cadillac DeVille Sedan FWD
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Maintenance & Repair
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