Replacement catalytic converter missing?

Wow, didn't that sound louder? Looks like they replaced your double cat with a single, which is typical, but they didn't replace the resonator (it was right where the two bars form an X). That can work, it's just not as quiet. You can still get another resonator and have it welded back in, they don't cost much.. You're getting the check engine light because they didn't replace the OEM valve that is incorporated into the dual cat system. It's vacuum activated and you should see the rubber hose for that dangling down there. It comes off a metal vacuum tube that leads up and runs across the engine compartment on the passenger's side. All you have to do is replace the vacuum canister that was mounted on the OEM cat to "trick" the system into thinking it's all working properly. That will get rid of the code.

You can actually lay the canister on top of the engine - splice into the vacuum line up there rather than extend the stub from below the car. Any sealed canister of approximately the same size works. One person here discovered a canister on old Honda motorcycles that you can find on Ebay. I've bought a couple of those and they work. However, I just bought another Prius this week and removed the cat. Offered the entire stock system to folks here and on Ebay but no takers, so I sold the cat yesterday for scrap. However, I kept the canister off it, just to have. You are welcome to it if you want to fix your code. Just LMK where to ship.

However, I'm not sure that all that is legal in OR. It's not in CA. You might require what is called a California-compliant cat in OR, or you replace with OEM parts. But, of course, Toyota doesn't have these parts anymore. The CA cats are pricey, if they even make one for Gen1. That's why so many CA Gen1s are totaled by the insurance companies when the cats are stolen, which I why I buy them for nothing and bring them to TX where we don't require those CA cats.

If you need to be compliant, LMK, I got another complete stock exhaust.

 

Here's a pic of the OEM exhaust. You can see the two-part cat at the bottom with the resonator behind them. Those two x-bars are supposed to go into those rubber grommets on each side of the resonator. That canister is between the two cats. A rod comes out of it to operate a valve that recirculates exhaust gases for a second pass through the cat.

 

Hi Ron,
You mentioned that you have another OEM exhaust system for sale. I'm interested. What is the price please?

Thanks,

 

$1100

 

Ok, I will think about it. Thank you.

 

OK. SYK, that's breakeven for me. I get $800 for the cat recyclers and will have to pay $300 to replace with the aftermarket cats they allow here in Texas. That car already has a salvage title, so no harm there, probably the one I end up keeping for myself. And really, cat prices are at real low right now. Could have got $1100 for them not long ago. I'd just rather see some of these old Prii saved. If you're thinking of junking yours because your cat got stolen, lmk.

 

Hello RonLewis. I am a new member here but have been poking around the forums for a couple of months. I bought a 2012 Prius this past summer and I have been putting it back together. I bought a Magnaflow exhaust part number 52543. I then went to have the exhaust swapped out. Low and behold I have the same setup as the original poster.

You mentioned that a Honda canister from a motorcycle would work to bypass this and satisfy the ECU. What part number is it by chance?

Thanks.

 

Here is the part number for the Honda goldwing cruse control vacuum control valve. 36520-MTZ-000.
There are quite a few available on ebay, or you can get a new one from a Honda motorcycle dealer.
I mounted mine up under the hood on the plastic panel on the engine coolant reservoir, then ran the vacuum line, that use to go down to the HCAC unit, to this.
It works great. No more 1436 and 1437 codes. And it looks pretty professional in that location.

If you drive in winter cold, just take in mind that one of the main purposes of the HCAC was to help bring the cats up to operating temperature and burn more efficiently on cold starts and warm up.

It's only happened to me a couple times in over 4 years, but if you start the car on a very cold winter morning and don't give it time to heat up, you might get a catalyst out of operational temperature code.
I just clear it and it doesn't come back, because it is now up to temperature.

 

Thank you so much!

A Goldwing, who would have thought.......that's something

 

Really, any canister with the same approximate volume would work the same. You could probably make one out of many materials - for example, PVC plumbing pipe. Cut a short length, glue caps on both ends, drill a hole and glue in a fitting for the vacuum line. I'm taking the OEM cats off my cars before someone steals them, so I think I can just take the OEM canister off and reuse it with an aftermarket cat. The recyclers don't want it.

 

So I have the device now. Which end goes where? I do not have the car in the air to look but will be taking it to a shop who will perform this replacement. Any advice is much appreciated

 

Hmm, do you refer to the new cat or the replacement cannister as the "device"? Since I'm swapping the OEM cannister, which is made of durable metal, to the aftermarket cats, I can just have the muffler shop tackweld it to the cat and use the existing vacuum hose right where it's at. If you've found some other type of canister, you can mount it almost anywhere you can run hose to. I've just laid those Goldwing cans on top of the engine, behind the air cleaner. Kinda blends in actually to look like OEM. If you'll follow that vacuum hose from below the car, it joins with two others in a triple bracket that's mounted against the firewall below the brake fluid reservoir, and comes up that side of the engine to it's destination on the throttle body. On the cars I've seen, it's the lowest hose in the triple bracket. So, you can grab it up there if you want to mount the cannister in the engine compartment. Bottom line: you need a hose from that throttle body sensor to your cannister.

If you're referring the the cat itself, that's pretty straightforward. Two bolts at the exhaust manifold, and two at the flange by the rear driver's side wheel. 14mm IIRC. Almost always real tough to break loose - an air hammer works great - but once broken they back out easy. They're holding a spring, so breaking it takes that tension off. Soak it real good in PB Blaster, etc.

I'm not going to lie to you - getting those bolts back in can be a pain. You have to compress the springs just a little to catch a thread and they're still springs. Once you get one side started, don't go in too many threads or it's hard to get the other side started. Of course, once you got both started, it's easy. Just tighten them down evenly.

There are two rubber bands holding the resonator in pace. A sawzall cuts right throught them, or any kind of handsaw. New ones are $5ea. at the auto parts. That's all you gotta do to swap an OEM cat assembly in/out. But you're going aftermarket, so more steps...

You gotta weld the aftermarket cat to the exhaust pipe in front of the resonator, where the old cat was. In fact, if yours was stolen, that's likely where the thief cut it, so your resonator, rubber bands, and rear flange bolts are all still fine. You just have to mount the cat to the engine's exhaust manifold flange and then have a muffer shop weld in a short pipe to connect them. If you want, you can buy flex pipe and u-clamps at the auto parts to do a temp fix - probably less than $20. It's OK that way, but the muffler shop should charge less than $100 to do the job permanently. and it'll be quieter, like OEM, with it welded. Then connect the vacuum line and install the oxygen sensor.

Total cost <$200

 

The Goldwing part. Thank you so much for the info. I appreciate it a lot

 

Tip: if you're working on the ground, jacking the car up, don't have an air/battery hammer, breaking those flange bolts can be tough. Hard to get leverage/long handle under there, and you need a long extension on the upper bolts, which gets kinda wobbly. But, I'm also an old man with weaker arms these days. A lotta guys would give up right there - the cramped space/risk/pain ain't worth it.

But, I've been able to use a ratchet strap on my ratchet handle to break these bolts (and others this way) pretty easily. Just gotta find (park next to) somewhere you can anchor the other end without losing your correct pull angle. I have a ratchet with a lip on the handle that kinda keeps the strap's hook from sliding off, if you can only catch an almost straight angle on the handle, but you can also use vice grips on the handle, lol. All that rig-up blows apart when the bolt breaks, but you don't need it but once and you're safely a few feet away with the ratchet. Tricky getting tension on all of it, correct angles, etc. to stay in place while you start cranking the ratchet, but the frustration is better than skinned knuckles and giving a shop $200.

A lift and air hammer make this real easy.