CATALYTIC CONVERTER OPTIONS (2 Viewers)

[YetiCruiser14]

I have been going back and forth with code P0420 for the past month. I replaced the upstream o2 sensor and the CEL went away for a month and it came back today in the freeway after a trail run. Downstream o2 sensor still looks okay that's why I didnt replace it with a new one but most of my research says that this code is due to a bad CAT. Any advise?

I know its hard to find a good condition Catalytic Converter but what's the best aftermarket option that will not break the bank.

Thank you and Happy 4th yall!

 

[LongDuck]

Downstream o2 sensor still looks okay

It's a lot cheaper to replace the downstream O2 sensor to match the new upstream one you've already done than buy a set of cats, but it's a WHOLE LOT easier to check the resistance of the downstream O2 sensor, first.

When you changed the upstream O2, the code went away. The easiest and cheapest thing would be to reset the code and see what happens - maybe something on your trail run moved a pending code to active. I'd work my way up from easy to $$$, and stop when the code stays off, but that's me.

 

[YetiCruiser14]

It's a lot cheaper to replace the downstream O2 sensor to match the new upstream one you've already done than buy a set of cats, but it's a WHOLE LOT easier to check the resistance of the downstream O2 sensor, first.

When you changed the upstream O2, the code went away. The easiest and cheapest thing would be to reset the code and see what happens - maybe something on your trail run moved a pending code to active. I'd work my way up from easy to $$$, and stop when the code stays off, but that's me.

Will get a new downstream o2 and see what happens.

yes the code went away when I changed my upstream o2 last month. So you are saying just reset the CEL and wait if it comes back again without doing anything aside from checking the tightness of both sensors?

 

[LongDuck]

That's what I'd do before buying another O2 sensor.

The ECU compares the downstream O2 reading from the upstream O2 and looks for a relative difference. There should be a difference because the oxygen has been reacted by the platinum core of the catalytic converter, so relatively less O2 should be read downstream. Changing your upstream O2 recently would give a good initial reference, and theoretically it should so a higher differential to the downstream O2 which is older - but who knows if it's accurate - if you can read real time data from OBD2, you can see each sensor on the fly.

Resetting the code is free, and I'm a big fan of free .

 

[YetiCruiser14]

Will do that. Thanks for your input!

 

[BILT4ME]

Will do that. Thanks for your input!

What year is your truck?

 

[YetiCruiser14]

What year is your truck?

It's a 95.

 

[LongDuck]

Good question, as I had to guess it's OBD2 based on his profile pic;

Weaponized autism can be a superpower.

 

[BILT4ME]

It's a 95.

I have very recently replaced my exhaust system, except for the resonator pipe.

I bought Magnaflow (and BRExhaust made by Magnaflow) from Summit Racing and I bought all hardware, gaskets, and cushions from Toyota.
The Magnaflow exhaust is all 409SS as well.
The original exhaust is 409SS.
I am working on my complete list of part numbers and pricing, and will post it in the next few days.
Mine is a 96 and will be identical to what you have.

 

[COS80]

I have very recently replaced my exhaust system, except for the resonator pipe.

I bought Magnaflow (and BRExhaust made by Magnaflow) from Summit Racing and I bought all hardware, gaskets, and cushions from Toyota.
The Magnaflow exhaust is all 409SS as well.
The original exhaust is 409SS.
I am working on my complete list of part numbers and pricing, and will post it in the next few days.
Mine is a 96 and will be identical to what you have.

That's a great price on that system, especially considering the ludicrous pricing local shops have quoted me (one was over $1,800 just for tweaks to the existing system). I wonder which wins for flow - 3" pipe with crush bends, or 2.5" (presumably the Magnaflow's pipe size) mandrel bent?

 

[BILT4ME]

That's a great price on that system, especially considering the ludicrous pricing local shops have quoted me (one was over $1,800 just for tweaks to the existing system). I wonder which wins for flow - 3" pipe with crush bends, or 2.5" (presumably the Magnaflow's pipe size) mandrel bent?

My old Magnaflow system to my new one.
Fit was excellent.
Still nice and quiet.
Changed out due to a cracked weld on muffler, rusted out bracket on muffler, and what was thought as a clogged cat.

89K miles in 6 years.

 

[ajax1]

I got code 420, reset the code, bout 6 months later wife complained of f lack of power and truck being loud, bout 8 months later cat clogged blew the y pipe, no power on the hwy. Replaced with used y pipe with 175k and two used cats.
Replaced your cats now

 

[YetiCruiser14]

Just want to post an update. I just replaced the upstream o2 sensor and rest the code with my scan gauge. Attaching pic of the old o2 sensor. Still looked okay appearance wise but replaced it anyways.

I am going to Holcomb Valley tomorrow for a daytrip hope everything goes well.

 

[efjayatee]

If not in CA Walker cats are super cheap

 

[YetiCruiser14]

If not in CA Walker cats are super cheap

I already got a quote from a muffler shop here in OC for $585 with install but its not magnaflow and for only 1 cat.

I also know a mechanic whos selling a 7year old CAT (which i dont know for sure if hes cappin) for $700.

If the CEL comes back i have no choice but to get a new cat since both o2 sensors have been replaced.

 

[efjayatee]

I already got a quote from a muffler shop here in OC for $585 with install but its not magnaflow and for only 1 cat.

I also know a mechanic whos selling a 7year old CAT (which i dont know for sure if hes cappin) for $700.

If the CEL comes back i have no choice but to get a new cat since both o2 sensors have been replaced.

Too bad ur in OC.
$300 for Walker rear and front. Cost me $80 to weld them on. Too early to say but P0420 is no more.

 

[Milkm4n]

Just failed my smog in SoCal, my magnaflow cats are less than 10 years old with less than 150k miles. Actually passed the sniffer test with flying colors but failed the visual as the technician can no longer read the EO laser etching....says I would need to replace them both. Goes to show the priority isn't really about clean air.

 

[efjayatee]

CA Smog test is a Scam!!

 

[efjayatee]

Just failed my smog in SoCal, my magnaflow cats are less than 10 years old with less than 150k miles. Actually passed the sniffer test with flying colors but failed the visual as the technician can no longer read the EO laser etching....says I would need to replace them both. Goes to show the priority isn't really about clean air.

View attachment 3947653

View attachment 3947654

Maybe a different shop?

 

[Milkm4n]

I have a 96 lx450 I bought with no engine odometer shows 100k miles, I mentioned removing the stock cats off that truck and installing them onto my 97 and the tech told me that's illegal. His explanation was catalytic converters are not supposed to be taken from one vehicle and installed on another even if you own both vehicles/not for resale. I find it plausible as diesel owners deal with Similar issues with def and catalytic converters deletes etc etc.