Bad maf trigger P0430

[Tnsilverado]

I have a 2018 silverado with the 5.3 and 5,000 miles. My truck is throwing a code P0430. I have a hard time believing the cat is bad. After hooking up my scan tool the oxygen sensors are switching as they should and the down stream sensors are steady and not mimicking the upstreams. One thing I did notice is my MAF is only reading 3.9g/s at idle and that’s at operating temp. Should this engine not be around 5.3-5.5 g/s? Could this cause the code? If anyone has any ideas I’d appreciate it  

[BO TIE 1]

Try cleaning the MAF sensor and clear codes to see if they return. 

[ember1205]

You have a six year old truck with 5,000 miles on it? 

 

Anyway, p0430 doesn't necessarily mean "bad cat", could mean bad O2 sensor.

 

Also, MAF values at idle can vary. I believe I was seeing around 5.5 on mine when operating correctly. You need to ALSO check the readings while there is load on the engine and it's at about 2000-2500 RPMS or so. You would want to compare the idle and higher RPM values to be sure it appears to be reading correctly.

[Tnsilverado]

Yes it actually had less than that when I bought it a month ago. The guy that originally bought it got it for a tax write off. Never drove it. Anyway I finally had an appointment at the dealer, it was the cat. They claimed it was clogged from all the short trips it made. They replaced it and all has been well.