P0420 and P0430

So it sounds like both my CATs are bad, I'm in SoCal near Anaheim and I'm going to sell the truck because im up to 235k miles on it. Know where or what company I can use to get them done?

 

Is P0420 definitely a bad cat? I have the same code.

 

No it’s not necessarily a bad cat. It could be something as simple as a leak from a bad exhaust gasket. P0420 codes can be a pain to diagnose

 

Try switching your sensors to confirm first.

I do have a stock set of OEM manifolds in the garage if they are hard to find.

 

Reason i think its a bad code is because i had a misfire a while back and replaced the spark plugs, and then both codes popped up so that's what i was assuming it was.

 

I always warn others, p0420/430 is rarely anything but cats. Especially on Tacomas, you'll see people suggest exhaust leaks, or sensors but its the cats.

The misfire likely accelerated their end, the cats don't like misfires or overfueling.

 

So replace the sensors first? And then go from there?

 

Check for leaks first. It’s the cheapest thing to do and gaskets are only a couple bucks if that’s what it is. Then test your sensors instead of going straight to replacing them cause they’re a bit pricey. There’s a bunch of videos on YouTube of how to do this. If all that checks out then test your cats, again there’s videos and articles online on how to do this. The most common method I’ve seen is using an infrared thermometer and checking the temps at the inlet and outlet of the cats.

 

If you only have one bank error then switch sides with the sensors to confirm if your problem is actually on that bank or just a bad sensor if it shows on the opposite bank after switching.

 

Both bank 1 and 2 are bad

 

Check for signs of soot that indicate exhaust leak around the manifold.

 

So if everything checks out to be the CATs, where is a good place to get them. Got a shop that'll do 1500 installed for both, not OEM. Or he said 300 to install if i bring him both

 

$1500 is a good deal. I had mine replaced on my FJ a couple years ago for about $1800 using MagnaFlow cats. CEL light hasn't come on since. Toyota wanted about 4K to replace them.

 

Not sure where “agua duice” is but for OEM is he talking about bringing in two cats or complete manifolds?

 

Agua Dulce is a little north of Santa Clarita, CA and he said 1500 for the manifold cats.

 

I have OEM cats on stock manifolds but my manifolds won’t fit your truck. I can cut off the cats on one end and they can just weld them up to your manifolds. Mine are off a 2014 with secondary air injection pipes which is why they won’t bolt up. I thought I saw yours was an 06.

 

Yeah mines an 06, so would that mean you need new CATs then?

 

Im fixing them to sell so whatever clears the code and passes smog I'm good with

 

No, the cats are the same, just the recirculating piping is different where the manifold mates up to the block. They can just weld on these cats to your manifold after cutting off your bad cats.

I don’t need/want cats up front. I run long tube headers, JFR y-pipe, 3” collector, magna cat back, resonator to a Dodge Ram 1500 muffler. I don’t have to deal with CARB.

 

These will work then, totally committing that it is your cats and not just a freak occurrence that both sensors failed at the same time.