Aftermarket cats

I’ve researched forums and videos like crazy without resolution to my problem, so perhaps many others are in the same boat.

I have a 2016 5.7 Tundra. I was 500 miles from home when my cats were stolen. I was not in a position to get them replaced with OEM cats and to get home I had no choice but to get aftermarket replacements. The dreaded check engine light plagues me, and downstream 02 codes persist. I used Midas, and multiple trips to my location location to try to rectify this have not fixed the issue. Hats off to them for standing behind their nationwide warranty. They have eliminated exhaust leaks, so they think and replaced an O2 sensor that appeared to have been damaged by the heat shield, but bank 1 sensor 2 downstream code persists.

I am concerned that the downstream sensors are effecting fuel trim, running rich, as highway mpgs have gone way down, though I’m in the camp that we don’t own Tundras for fuel efficiency. There is conflicting info as to whether downstreams effect fuel trim.

Also concerning is when it comes time to trade in, I will surely be hosed by the check engine light.

I have tried non foulers, and currently am receiving bank 1 sensor 2 code, so think that perhaps bank 2 sensor 2 is corrected by the non fouler. I’ve tried a small ball of steel wool in both, but still have bank 1 sensor 2 code.

Question, do the downstream sensors effect the ECU fuel map? And has anyone successfully fixed this issue with aftermarket cats? I’m reluctant to try to force insurance to replace with OEM if fixing with aftermarket cats is possible, and reluctant to have Midas chase an unfixable problem as well. Has anyone had luck with 90 degree non foulers? I’m considering JB Weld high temp at the non fouler tip and drilling a smaller hole to attempt to allow a smaller amount of exhaust fumes to reach the downstream O2 sensors.

Anyone who has had success with aftermarket cats, would appreciate your experience. I know there are many threads related to the growing thievery, but OEM cats seem to be the only fix, though I hope I can proceed with what should be perfectly good cats.

 

From what I’ve seen, aftermarket seem to have some issues one way or another. Not saying it would be your issue, just what I’ve seen. Some people have had success