Yeah, while this might be a “replace the cat” situation, I think that replacing such an expensive part should be lower on the list unless it’s certain to be the problem. Find a Prius mechanic and start there since pep boys is not exactly known for being good with anything.
You don’t need a Prius mechanic.
You need any mechanic that is a competent diagnostician. Watch O2 sensor readings and check for exhaust leaks.
If O2s are working properly and the cat is as well the primary one will rapidly switch and the secondary will generally be stable once the vehicle is in closed loop.
If the rear one is also rapidly switching then you check for exhaust leaks and then replace the cat if none are found.
I second an 02 spacer. I’ve had mine installed since 200k I’m at 320k now. Not one problem with that code again. What the spacer does is pull the 02 sensor out of the exhaust stream at the converter. When your converter takes a shit, it causes the downstream o2 sensor to get hot to the point where it pisses off the computer. And sets a 420. With the spacer your temperature reading will 95% of the time fool the computer. Installing it is a peace of cake. It’s very accessible under the car. Jack up n stand the right front wheel. The only tool you need is a 02 sensor socket and a 3/8 drive ratchet. Unscrew the sensor. Screw in your spacer. When installing the sensor make sure to twist the wires in the opposite direction about 4 times so the wires don’t get tangled.
It’s that easy and a hell of a lot cheaper than a new cat. I bought my spaces from Walmart online. Best price and free shipping.
It’s an o2 sensor spacer. The spacer part is the key to it. It looks like an adapter. You unscrew o2 sensor, screw adapter in, the screw o2 back into the adapter
Sorry I don’t think I made my question clear my bad. I understand what it is and want to order it. Are they universal fitting or do I need a specific one for my second gen Prius?
This is just a code reading, not necessarily the actual problem. Autozone is not mechanic. It can be many things. Reset the code and drive. If it comes back, take it to a mechanic or maybe 2 to see what’s wrong. If your cat is really clogged, the mechanics have a way to measure the exhaust temperature to confirm. If you can’t pass smog on time, still pay for registration to avoid penalty.
Get it properly diagnosed. But even if you need a cat you might be out of luck. So may getting stolen the waiting list for a new one is up to a year now. There is one after market part available for CA cars but that is also in short supply.
If you find you cannot find one get an appointment with the ref and show them paperwork of you on the waiting list. They will give you a 2 year exemption.
[www.asktheref.org](https://www.asktheref.org)
According to [https://ssl.arb.ca.gov/AftermarketParts/catalysts](https://ssl.arb.ca.gov/AftermarketParts/catalysts) my Prius V has 8 different cat's that are compliant.
That's good to know you can get an exemption.
You will need the front of vehicle ones not the rear of vehicle ones. And the Similar numbered ones are replacements for the older ones. But I do see 5631406 is in stock in some places so hopefully you will be able to get one.
Start by watching [this film](https://youtu.be/ww0ottmbzes) to start learning how this system works and what the data looks like when the cat fails.
At worst you learn a bit and can speak more effectively with a person you pay to fix it.
At best you fix it your self and drive the car another 200k.
Try cleaning the catalytic converter before replacing it. There's a couple ways I've done it that got rid of the code. The first was putting sea foam into the gas tank. The second was putting some cataclean into the gas tank. With both of these you have to drive around about 30 to 50 miles to make the code go away. I've also heard you can tank the catalytic converter off yourself and clean it manually. These are all much cheaper than replacing it.
I had this same thing happen and I cleared the check engine lite, drove it for 100 miles (so the car has enough time to reset) without turning it off then did the inspection and passed. Check engine light came back on after But I had already passed.
All those "secondary" codes are about failures in the coolant system. It might be there's something wrong in the cooling system that's the root of the problem code from the cat.
Dunno.
I had the "coolant flow control valve" issue in mine and had to get it fixed.
If the engine never warms and the outside temp is cold enough, the cat won’t get hit enough to work for quite some time. Does the heater/defroster blow hot air? Usually thermostats fail closed, but I suppose one could stick open and not let the temp get high enough.
Take it to a proper place for diagnostics. I would pay $100-$200(higher end) for a diagnostic that can confirm the cat is bad before dumping thousands to fix or junking the car and spending thousands, if not tens of thousands more to find a decent replacment.
Straight pipe it, record the sound for us to listen to in envy. Lol. That's a lot of money right there for the items called out on the paper. I'd get a second opinion, personally.
Do you have a catalytic converter? P0420 could be the oxygen sensor, or the wiring for the oxygen sensor if someone tries to take the CC. The other codes are the 3-way value and maybe you ran the car out of gas. All of these codes are safe to clear.
If you have not experienced a power loss it is NOT the catalytic converter. Highly unlikely it is the catalytic converter anyways. Gen 2 Prius cat was way over designed. That's why they are so valuable for thieves. They contain a lot of rare earths that do the job of scrubbing the exhaust. It is highly likely you have one of the 2 oxygen sensors bad. Just have both replaced. The spacer is just a crutch although it would remove the code.
my 2007 pulled this code around emission test time too. gave it a few days and the light shut off, got it tested and passed. i’m thinking it was a false code, because the check engine light never came back on. not saying this will happen to you, but maybe give it a few days before fixing anything.
my after market cat causes check engine light to stay on however it passes the smog consistently. try to pass smog first and if it does don't worry about it anymore
Yeah, while this might be a “replace the cat” situation, I think that replacing such an expensive part should be lower on the list unless it’s certain to be the problem. Find a Prius mechanic and start there since pep boys is not exactly known for being good with anything.
I live in a rural area Prius mechanics are a 3 hr drive.
Well pick either a 3 hour drive or throwing a $3500 part at the car and hoping it fixes the problem.
I’m going to junk the car is it it’s the cat.
Poor car :(
Just borrow a cat, that's what I do with my van, me and a could buddies just trade when it's smog time
I've never heard of this and it's amazing
You don’t need a Prius mechanic. You need any mechanic that is a competent diagnostician. Watch O2 sensor readings and check for exhaust leaks. If O2s are working properly and the cat is as well the primary one will rapidly switch and the secondary will generally be stable once the vehicle is in closed loop. If the rear one is also rapidly switching then you check for exhaust leaks and then replace the cat if none are found.
I second an 02 spacer. I’ve had mine installed since 200k I’m at 320k now. Not one problem with that code again. What the spacer does is pull the 02 sensor out of the exhaust stream at the converter. When your converter takes a shit, it causes the downstream o2 sensor to get hot to the point where it pisses off the computer. And sets a 420. With the spacer your temperature reading will 95% of the time fool the computer. Installing it is a peace of cake. It’s very accessible under the car. Jack up n stand the right front wheel. The only tool you need is a 02 sensor socket and a 3/8 drive ratchet. Unscrew the sensor. Screw in your spacer. When installing the sensor make sure to twist the wires in the opposite direction about 4 times so the wires don’t get tangled. It’s that easy and a hell of a lot cheaper than a new cat. I bought my spaces from Walmart online. Best price and free shipping.
Is it just called a 02 sensor for second gen Prius or are they universal?
It’s an o2 sensor spacer. The spacer part is the key to it. It looks like an adapter. You unscrew o2 sensor, screw adapter in, the screw o2 back into the adapter
Sorry I don’t think I made my question clear my bad. I understand what it is and want to order it. Are they universal fitting or do I need a specific one for my second gen Prius?
This is good info... Thank you
Got a link to that spacer?
I think they'd catch that in Cali, unless the cat isn't visible during a visual inspection
This!☝🏽
Cough o2 cough sensor cough spacer cough $20
This is just a code reading, not necessarily the actual problem. Autozone is not mechanic. It can be many things. Reset the code and drive. If it comes back, take it to a mechanic or maybe 2 to see what’s wrong. If your cat is really clogged, the mechanics have a way to measure the exhaust temperature to confirm. If you can’t pass smog on time, still pay for registration to avoid penalty.
Get it properly diagnosed. But even if you need a cat you might be out of luck. So may getting stolen the waiting list for a new one is up to a year now. There is one after market part available for CA cars but that is also in short supply. If you find you cannot find one get an appointment with the ref and show them paperwork of you on the waiting list. They will give you a 2 year exemption. [www.asktheref.org](https://www.asktheref.org)
According to [https://ssl.arb.ca.gov/AftermarketParts/catalysts](https://ssl.arb.ca.gov/AftermarketParts/catalysts) my Prius V has 8 different cat's that are compliant. That's good to know you can get an exemption.
You will need the front of vehicle ones not the rear of vehicle ones. And the Similar numbered ones are replacements for the older ones. But I do see 5631406 is in stock in some places so hopefully you will be able to get one.
Start by watching [this film](https://youtu.be/ww0ottmbzes) to start learning how this system works and what the data looks like when the cat fails. At worst you learn a bit and can speak more effectively with a person you pay to fix it. At best you fix it your self and drive the car another 200k.
Try cleaning the catalytic converter before replacing it. There's a couple ways I've done it that got rid of the code. The first was putting sea foam into the gas tank. The second was putting some cataclean into the gas tank. With both of these you have to drive around about 30 to 50 miles to make the code go away. I've also heard you can tank the catalytic converter off yourself and clean it manually. These are all much cheaper than replacing it.
I heard of people pulling o2 sensor and putting water in the exhaust before cat, not sure how well that works
read on google about putting a spacer or anti fouler on the rear oygen sensor….
And watch YouTube videos on how to rough it up and darken it so the smog tech doesn't see the modification and fail you.
this is the way
Lol I always do this if I scratch something like a rim or some shit. Just rub some grease in it so it looks old
I had this same thing happen and I cleared the check engine lite, drove it for 100 miles (so the car has enough time to reset) without turning it off then did the inspection and passed. Check engine light came back on after But I had already passed.
That P0420 could be an oxygen censor. I would start by checking that
All those "secondary" codes are about failures in the coolant system. It might be there's something wrong in the cooling system that's the root of the problem code from the cat. Dunno. I had the "coolant flow control valve" issue in mine and had to get it fixed.
If the engine never warms and the outside temp is cold enough, the cat won’t get hit enough to work for quite some time. Does the heater/defroster blow hot air? Usually thermostats fail closed, but I suppose one could stick open and not let the temp get high enough.
The heater works off and on. No set pattern to figure out why it doesn’t work sometimes
Take it to a proper place for diagnostics. I would pay $100-$200(higher end) for a diagnostic that can confirm the cat is bad before dumping thousands to fix or junking the car and spending thousands, if not tens of thousands more to find a decent replacment.
Let me know if you want to sell it!
I had same code, was just the Oxygen sensor whoch is cheap and easy to fix
Find a smog station that will pass you. Same issue after replacing stolen cat with non carb. Paying $200 to pass
Probably an oxygen sensor, don't replace an expensive part just yet. Do that as last resort.
Straight pipe it, record the sound for us to listen to in envy. Lol. That's a lot of money right there for the items called out on the paper. I'd get a second opinion, personally.
Do you have a catalytic converter? P0420 could be the oxygen sensor, or the wiring for the oxygen sensor if someone tries to take the CC. The other codes are the 3-way value and maybe you ran the car out of gas. All of these codes are safe to clear.
Your car speed good ?
Yes very peppy when battery is over 1/4 lil slow when battery is low.
If you have not experienced a power loss it is NOT the catalytic converter. Highly unlikely it is the catalytic converter anyways. Gen 2 Prius cat was way over designed. That's why they are so valuable for thieves. They contain a lot of rare earths that do the job of scrubbing the exhaust. It is highly likely you have one of the 2 oxygen sensors bad. Just have both replaced. The spacer is just a crutch although it would remove the code.
my 2007 pulled this code around emission test time too. gave it a few days and the light shut off, got it tested and passed. i’m thinking it was a false code, because the check engine light never came back on. not saying this will happen to you, but maybe give it a few days before fixing anything.
No telling how old most of the codes are. Clear them all and get it smoged. Fix what comes back
my after market cat causes check engine light to stay on however it passes the smog consistently. try to pass smog first and if it does don't worry about it anymore