Does Colorado actually require that you have an OEM Catalyst? That upper cat with the HCAC might be worth getting a hold of. That "Air Valve" is very hard to come by, and if you actually find a whole Cat assembly for a Gen 1, new from the dealer, you are very lucky to find a dealer with old discontinued stock. The cats were stolen off my 2003 Gen 1 and I did a very in-depth search for the OEM Gen 1 cats from Toyota, and used, and aftermarket. I discovered that the Cat Assembly is now a discontinued part. The search for used assemblies found either junk or way over-priced listings, and there is no aftermarket unit made that has the HCAC unit on it. The 2002 to 2009 Cats fit the Gen 1 perfectly, but without the HCAC, I picked up a Honda Goldwing Cruise Control Vacuum Pot and installed it on the vacuum line. It adequately simulates that action of the HCAC vacuum pot. Otherwise, you will get trouble codes for the missing HCAC of either the vacuum being open if you do not plug the line there, or for the vacuum being closed if the line is plugged but there is no vacuum pot action. The ECU can sense that there is no variation in the HCAC vacuum pot and so it throws a trouble code. I found an aftermarket EPA approved Cat Assembly for the 2004 - 2009 through eBay. It fits perfectly, and the tailpipe emissions readings are well within CARB requirements. Getting close to 2 years with it and there have been no trouble codes and the absolutely no change in the emissions readings, which I recently got just for curiosity's sake to monitor the performance and quality of the aftermarket assembly. I hope my story here has been helpful and that you get a good Cat assembly. That 2002 Gen 1 is quite a special car. My 2003 has quickly become my favorite car. It is fun, reliable, economical, and a joy for me to drive around in the mountains.
Replacing stolen catalytic converter(s)
Hello, all. I bought a Gen1 Prius when I was basically desperate for a car. Got ripped off by a guy who told/showed me all the great features of a Prius but conveniently forgot to say the cat(s) had been stolen.
I’ve been looking on/off for a week trying to replace what was taken. I’ve only found a front cat and the “air valve”, not what appears to be a 2nd cat—one article called it an “HC adsorber”. Toyota dealer and local muffler shops said $3500 to replace. Separate front cats seem to go for $200 up. Air valve is $300 from dealer. Haven’t found the adsorber. Neither has any local auto parts store. And CO emissions said it’s against federal laws to sell used cats.
Does anyone know how to find a whole assembly? I’ve seen them for $60 to 150 for 2004-2009 Priuses. I’m hoping one of those would fit on this car, and work as a temp solution.
Thanks!
I’ve been looking on/off for a week trying to replace what was taken. I’ve only found a front cat and the “air valve”, not what appears to be a 2nd cat—one article called it an “HC adsorber”. Toyota dealer and local muffler shops said $3500 to replace. Separate front cats seem to go for $200 up. Air valve is $300 from dealer. Haven’t found the adsorber. Neither has any local auto parts store. And CO emissions said it’s against federal laws to sell used cats.
Does anyone know how to find a whole assembly? I’ve seen them for $60 to 150 for 2004-2009 Priuses. I’m hoping one of those would fit on this car, and work as a temp solution.
Thanks!
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Bruce:
Wow, thank you for the comprehensive reply!
I had already ordered a cat & resonator assembly from Amazon that fits 04-09 Priuses, thinking that it would give me two cats or one plus a resonator. Intuition said it would fit. I’ve seen lots of these assemblies, but no explanation of what they are.
I talked to an CO emissions tech yesterday, but he didn’t say if they require documentation of all parts being OEM or Colorado-compliant. If they don’t, and it does pass the test (with the air-valve you’re saying could be cleverly replaced with the Gold Wing part), then I perhaps I will be done. First set of parts will be here tomor (cat assembly and new O2 sensor). Thanks again for crucial info to help my waning optimism.
Nov8v
PS. I’m glad to hear it’s a worthwhile car! I liked it a lot when I drove it. Quick handling, regen braking, decent stereo. And [CkEng] light was off. Thieves know how to clear those codes, I recall now.
Thanks again, sir. You’re a gentleman and a scholar. 👍🏼 🙏🏼
Wow, thank you for the comprehensive reply!
I had already ordered a cat & resonator assembly from Amazon that fits 04-09 Priuses, thinking that it would give me two cats or one plus a resonator. Intuition said it would fit. I’ve seen lots of these assemblies, but no explanation of what they are.
I talked to an CO emissions tech yesterday, but he didn’t say if they require documentation of all parts being OEM or Colorado-compliant. If they don’t, and it does pass the test (with the air-valve you’re saying could be cleverly replaced with the Gold Wing part), then I perhaps I will be done. First set of parts will be here tomor (cat assembly and new O2 sensor). Thanks again for crucial info to help my waning optimism.
Nov8v
PS. I’m glad to hear it’s a worthwhile car! I liked it a lot when I drove it. Quick handling, regen braking, decent stereo. And [CkEng] light was off. Thieves know how to clear those codes, I recall now.
Thanks again, sir. You’re a gentleman and a scholar. 👍🏼 🙏🏼
The reason for the lack of running in EV is almost certainly due to a bad 12volt battery and/or a bad terminal or ground point.
The 12volt battery does not turn over your engine as in a traditional car, your car does not have a starter, The HV battery and HV Motor are what starts the engine.
What the 12volt battery does is boot up all of the ECUs and support some accessories.
If the rested battery voltage is under 12.3 volts, the ECUs cannot boot up properly, which can cause all kinds of codes and false codes.
Also, when the battery is bad with low voltage and/or bad resistance, and the HV Battery, Generator, and Inverter are what charges the 12v battery, that bad battery is causing the HV system to continually have to work to charge it.
This, as with any draw, will cause the engine to run more often, maybe even constantly.
For instance, if I run my A/C fan on high with the A/C turned on, that creates enough draw that my engine runs much more constantly.
When I slow down or come to a stop and turn off the fan and A/C, the engine turns off.
The system on this car is designed to balance the engine and the electric to run at its most efficient, so if you are watching your power screen as you drive, you will see the screen showing it running on electric to engine + electric to engine in what looks like random ways, and possibly in ways that don't make sense to you. Don't worry, the system is doing its job.
The 12volt battery does not turn over your engine as in a traditional car, your car does not have a starter, The HV battery and HV Motor are what starts the engine.
What the 12volt battery does is boot up all of the ECUs and support some accessories.
If the rested battery voltage is under 12.3 volts, the ECUs cannot boot up properly, which can cause all kinds of codes and false codes.
Also, when the battery is bad with low voltage and/or bad resistance, and the HV Battery, Generator, and Inverter are what charges the 12v battery, that bad battery is causing the HV system to continually have to work to charge it.
This, as with any draw, will cause the engine to run more often, maybe even constantly.
For instance, if I run my A/C fan on high with the A/C turned on, that creates enough draw that my engine runs much more constantly.
When I slow down or come to a stop and turn off the fan and A/C, the engine turns off.
The system on this car is designed to balance the engine and the electric to run at its most efficient, so if you are watching your power screen as you drive, you will see the screen showing it running on electric to engine + electric to engine in what looks like random ways, and possibly in ways that don't make sense to you. Don't worry, the system is doing its job.
Hello again:
I installed the new cat assembly last Saturday. It’s for an 04-09 Prius, but fits into this car perfectly. $50.
Car runs quieter. And as long as the aux batt stays charged, it runs in EV mode when it can. Haven’t even connected the O2, whose cable the thieves cut.
I no longer curse this vehicle. I pat it gently on the dashboard, thanking it and saying a prayer of gratitude. I liked from the moment I got behind the wheel.
Thanks again, Bruce.
You improved my life!
ImNov8v
PS. Do you have a part number for
that Goldwing valve/pot?
I installed the new cat assembly last Saturday. It’s for an 04-09 Prius, but fits into this car perfectly. $50.
Car runs quieter. And as long as the aux batt stays charged, it runs in EV mode when it can. Haven’t even connected the O2, whose cable the thieves cut.
I no longer curse this vehicle. I pat it gently on the dashboard, thanking it and saying a prayer of gratitude. I liked from the moment I got behind the wheel.
Thanks again, Bruce.
You improved my life!
ImNov8v
PS. Do you have a part number for
that Goldwing valve/pot?
I replaced the downstream O2 sensor. It immediately used the EV-drive instead of ICE-drive while in Reverse. Nice surprise.
I took it to the state emissions testing place, and it PASSED. I didn’t think it would, because I just plugged the vacuum tube (used to go to that “air valve” that Toyota wants $300 for). That’s the one that BruceBerquist_3929 replaced with <a Goldwing pot>. I didn’t look for it, because I couldn’t fathom how a “pot” (potentiometer?) could be connected to a vacuum tube. Maybe there’s an electrical connection that got cut when the cat /adsorber /air-valve were stolen?
Thanks!
I took it to the state emissions testing place, and it PASSED. I didn’t think it would, because I just plugged the vacuum tube (used to go to that “air valve” that Toyota wants $300 for). That’s the one that BruceBerquist_3929 replaced with <a Goldwing pot>. I didn’t look for it, because I couldn’t fathom how a “pot” (potentiometer?) could be connected to a vacuum tube. Maybe there’s an electrical connection that got cut when the cat /adsorber /air-valve were stolen?
Thanks!
We bought a 2010 Prius about 3.5 years ago, excellent condition, with low miles. So far, I've replaced:
Traction battery $2440, 12V battery, $200, tires, $700, and had the EGR system completely purged, with 2 new parts, $1800, rear brakes done, $200. It hasn't exactly been the cheapest car to drive, but I never worry about it breaking down on us. The oil is changed every 5,000 miles. The gas mileage ranges between 47 and 52 mpg.
Usually, when a Prius owner sells or trades one off, they consider it to be at the point where it's gonna start losing money for them.
Traction battery $2440, 12V battery, $200, tires, $700, and had the EGR system completely purged, with 2 new parts, $1800, rear brakes done, $200. It hasn't exactly been the cheapest car to drive, but I never worry about it breaking down on us. The oil is changed every 5,000 miles. The gas mileage ranges between 47 and 52 mpg.
Usually, when a Prius owner sells or trades one off, they consider it to be at the point where it's gonna start losing money for them.
Wow, that’s a lot of maintenance.
But that’s a much newer vehicle with
fewer miles. You sound dedicated to
driving it quite a while longer.
But that’s a much newer vehicle with
fewer miles. You sound dedicated to
driving it quite a while longer.
1 - 8 of 8 Posts
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