@bd3616 for now, go ahead and replace the gas cap. It is absolutely possible that this trips the P0420 code (more common would be a code for a leak in the EVAP system. Those would be P0442, P0443, P0446 for your Volvo) after a while. It is a pretty generic code with lots of possibilities. It is possible that you CAT was worn out but it appears they threw everything but the kitchen sink into that repair and replaced all of the parts that could cause that code. We really can't second guess your mechanic on that since we just simply don't know. Personally, I have not worn out a CAT even with all my high mileage vehicles. Lot's of O2 sensors and lots of gas caps, but never a Catalytic Converter.
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@bd3616 for now, go ahead and replace the gas cap. It is absolutely possible that this trips the P0420 code (more common would be a code for a leak in the EVAP system. Those would be P0442, P0443, P0446 for your Volvo) after a while. It is a pretty generic code with lots of possibilities. It is possible that you CAT was worn out but it appears they threw everything but the kitchen sink into that repair and replaced all of the parts that could cause that code. We really can't second guess your mechanic on that since we just simply don't know. Personally, I have not worn out a CAT even with all my high mileage vehicles. Lot's of O2 sensors and lots of gas caps, but never a Catalytic Converter. After 2 years (you did not tell us how many miles) it should not have worn out again. Your O2 sensors are usually good for something like 100k miles as well. Anything that messes with the Fuel/air ratio can cause this. Something like a faulty Fuel Pressure Sensor etc. must be considered.
Let us know what happens when you change the gas cap and drive a few miles :-) Best of luck
@bd3616 for now, go ahead and replace the gas cap. It is absolutely possible that this trips the P0420 code (more common would be a code for a leak in the EVAP system) after a while. It is a pretty generic code with lots of possibilities. It is possible that you CAT was worn out but it appears they threw everything but the kitchen sink into that repair and replaced all of the parts that could cause that code. We really can't second guess your mechanic on that since we just simply don't know. Personally, I have not worn out a CAT even with all my high mileage vehicles. Lot's of O2 sensors and lots of gas caps, but never a Catalytic Converter.
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@bd3616 for now, go ahead and replace the gas cap. It is absolutely possible that this trips the P0420 code (more common would be a code for a leak in the EVAP system. Those would be P0442, P0443, P0446 for your Volvo) after a while. It is a pretty generic code with lots of possibilities. It is possible that you CAT was worn out but it appears they threw everything but the kitchen sink into that repair and replaced all of the parts that could cause that code. We really can't second guess your mechanic on that since we just simply don't know. Personally, I have not worn out a CAT even with all my high mileage vehicles. Lot's of O2 sensors and lots of gas caps, but never a Catalytic Converter.
Let us know what happens when you change the gas cap and drive a few miles :-) Best of luck
@bd3616 for now, go ahead and replace the gas cap. It is absolutely possible that this trips the P0420 code. It is a pretty generic code with lots of possibilities. It is possible that you CAT was worn out but it appears they threw everything but the kitchen sink into that repair and replaced all of the parts that could cause that code. We really can't second guess your mechanic on that since we just simply don't know. Personally, I have not worn out a CAT even with all my high mileage vehicles. Lot's of O2 sensors and lots of gas caps, but never a Catalytic Converter.
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@bd3616 for now, go ahead and replace the gas cap. It is absolutely possible that this trips the P0420 code (more common would be a code for a leak in the EVAP system) after a while. It is a pretty generic code with lots of possibilities. It is possible that you CAT was worn out but it appears they threw everything but the kitchen sink into that repair and replaced all of the parts that could cause that code. We really can't second guess your mechanic on that since we just simply don't know. Personally, I have not worn out a CAT even with all my high mileage vehicles. Lot's of O2 sensors and lots of gas caps, but never a Catalytic Converter.
Let us know what happens when you change the gas cap and drive a few miles :-) Best of luck
@bd3616 for now, go ahead and replace the gas cap. It is absolutely possible that this trips the P0420 code. It is a pretty generic code with lots of possibilities. It is possible that you CAT was worn out but it appears they threw everything but the kitchen sink into that repair and replaced all of the parts that could cause that code. We really can't second guess your mechanic on that since we just simply don't know. Personally, I have not worn out a CAT even with all my high mileage vehicles. Lot's of O2 sensors and lots of gas caps, but never a Catalytic Converter.
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Let us know what happens when you change the gas cap and drive a few miles :-) Best of luck
@bd3616 for now, go ahead and replace the gas cap. It is absolutely possible that this trips the P0420 code. It is a pretty generic code with lots of possibilities. It is possible that you CAT was worn out but it appears they threw everything but the kitchen sink into that repair and replaced all of the parts that could cause that code. We really can't second guess your mechanic on that since we just simply don't know. Personally, I have not worn out a CAT even with all my high mileage vehicles. Lot's of O2 sensors and lots of gas caps, but never a Catalytic Converter.