Hello, my name is Ray.

I have a 2020 f150 5l.I have a had a check engine light for about 5 months with a slightly rough idle on my truck.Initially only for the left side now which I replaced,but it didn't resolve the check engine light.I recently had it diagnosed at my dealership which suggested replacing both CATs including the new one as they are both below efficiency.Should I get new cats?or is the issue likely to be something else (o2 sensors,fuel injectors,ignition coils) etc.?
Thanks Everyone in advance.
Sorry if it's a common post new to the forums.

 

If the converter you replaced is less than 5 months old, assuming it is a Ford part, it should be under warranty.

 

Its AP eastern i purchased it from rockauto parts.

 

AP claims a 5 year/50k mile warranty on their cats. I'd contact them and use the dealer's diagnostics as reason for why you want it replaced.

I've had terrible luck with aftermarket cats. I know the OEM ones are very expensive but they really are much better quality.