2022 F250 XLT 7.3 CCSB 20,308 miles.
I'm in Arizona today, a 325 mile trip with nothing behind me. This morning I drive from my hotel to my cousins for breakfast and football. I fire up to go back to our hotel ang get a check engine light. WTH? Drive over to Vato Zone for a code reading and get P0340, Cat efficiency below threshold, solution, replace cat. WTF, no way. All I can say that was odd is that in a lot of the greater Phoenix area, driveway approaches are a little more abrupt than what I am used to in SoCal. I did bump one a little hard leaving before I noticed the CEL. I can't believe that on a 4wd truck that that little bump could upset something enough to trip the CEL. I did reset the CEL at Vato Zone and didn't have any issues with 4 more starts and 25 miles. Anyway, Cool Sory Bro. Anyone ever get anything goofy like this show up?

 

Welcome to the world of electronics...lol My CEL was different than yours. Right after I drove out of the 60k powertrain warranty period I had a CEL come on for low coolant temp. Lots of suggestions here to replace the thermostats. I reset the code and I have put another 15,000 miles on the truck and the code never came back, and never had an actual performance problem.

 

The code you list is cam position sensor, maybe you remembered it wrong.

 

I'll have to double check. The text was the cat efficiency blah, blah, blah.

 

P0430 is bank 2 catalyst inefficiency. My '20 7.3 started throwing it at ~19k miles. Cleared it, was good for a week then came back. Cleared it, then a week later got both p0430's and p0420's (bank 2 and 1)
Dealer replaced the cats (Y pipe) and it's been good ever since. Talked to our local Ford FSE about it, it's more common than you'd think. Funny they seem to fail around the ~20k mile mark.

 

Yeah, it popped back up this morning on start up. I'll call the dealer when I get home. What a pain in the ***. I guess it could be worse, could be a shot CP4 pump.

ETA: Service appt. scheduled for Tuesday. Wish me luck.

 

So on the 25th, I moved about 6-7 miles, shut down and the CEL clears on start up and has been off for 200 miles and 8-9 start ups or key cycles. I cancelled my appointment since I really need my truck.
BTW, the Ford app tells me the P0340 is a cat problem.

 

Well, at least if the cat is going bad, it’ll fall under the emissions warranty.

 

And it's back. Now P0420 and P0430 and these codes cleared themselves again. WTH? I took it in to the dealer, what a disappointment. I did the relay mod in the air actuated locking hubs so I would have 2wd low. They couldn't seem to get past that and check the emissions system. The 2wd low mod is not new. It's been about 9 months since I did it. I had a conversation with a very recently retired Ford mechanic. His short opinion? The tech that looked at the truck is an idiot. They asked me to return the truck to stock and see if the fault returns.
I'm not the sharpest knife in the drawer but I don't see how the two are vaguely related. I'm going to have to check into the thread here where I found the tip about the 2wd low mod.

 

Time to gut the cats and trick the O2 sensors! Ahhh, the good 'ol days....

 

I second that opinion,…..😂 Gutted many a cat and slapped em’ back in with a coat hanger and torch,……. aaaah the good ol’ days is right.

Secondly, can’t believe the tech on this one,….2WD low / cats? Ridiculous,…. me being ex-military and worked Construction ever since, ida whispered into the tech’s ear, “come out backside of this building with me a minute, and let’s me and you have a quick talk”,….with a big smile on my face the whole time.
As I get older,…..reckon I’m getting a little less tolerable/ patient,…. if I smell the slightest hint of BS, I immediately call it,……me and that ol’ boy woulda went round-and-round right there and then,…not physically, but thankfully I know enough to go round,….now, go do your job under the warranty I payed for and stop muckin’ around.

I know you said you need your truck, but I’d be walking my *** right back in there. Aggravates me when I hear responses like that from techs / Service Managers,…. flips a switch on me for some reason😂

Apologies for the rant fellars, sitting on my back porch with my first coffee and cigar this morning,,,,when I read this post, it aggravated me a bit,…apologies men.

 

Better check, Ain’t got no cat in it.

 

There he goes again,……read what srkr wrote,…in the Karl from Sling Blade voice,…..uuuuuhuh😂 funny dude, just funny - keep hitting that grin button bud, yer good at it.

 

**UPDATE**
Bad bank 2 cat. Replaced along with Y-pipe and all hardware. Took it in on Monday the 13th, got it back Friday the 17th.
What was aggravating was I texted about 2 for an update and was told my truck was ready. I wonder if I would have texted at 10 would it have been ready. So I get there and wait nearly 30 minutes for a porter to bring my truck around. They all move like they're under water. When my truck finally shows up the check engine light is on. WTF!!?? I had to wait another 20 minutes while they tried to get a tech to look at it. Took it into the black hole and came out 5 minutes later and said the last dummy to work on it forgot to clear the code. How the hell does that happen? If I need anymore warranty work done I think I'll find another dealer.
So do I dump my truck when the warranty expires? I don't want to be paying for cats after that. Hell, my last truck had good cats for 225k miles until I sold it then it was stolen.

 

Nowadays, anything can suffer just being made wrong. Bad parts are more common it seems. Good luck and hope it does not happen again...