Catalytic converter: OEM vs. Universal

I bought the magnaflow catalytic converter and it's a perfect fit for the Prius, sold on Amazon for $100. Cost me $40 to weld it on but most people I've read about got it installed for around $80-$150

Magnaflow 99205HM Universal Catalytic Converter (Non CARB compliant)

 

$235 Doesn't seem bad, especially if it's a perfect fit from the get go.

 

The one that goes bad is usually the one that's closest to the manifold. You just cut off the old one and weld on the new one. No need to do anything with the oxygen sensor

 

I'm going through this fiasco right now as well. Just got back from the muffler shop. You need to find out what type of emissions your car is compliant with. CARB i.e. California or non-CARB. From my understanding if your car is CARB compliant the cheap replacement cats won't work and your check engine light will stay on. You'll need to get a CARB compliant catalytic converter.

 

Vehicles licensed outside of California, but built to California emissions standards, may have a physical difference from a vehicle built to Federal emissions standards. (If your vehicle is manufactured to California emissions standards, it cannot use a converter that is cataloged as Federal only). You need to reference your vehicles emissions sticker before purchasing a Walker converter. A vehicle licensed in the State of California must use a CARB approved converter.

WALKER® EXHAUST SYSTEMS :: Catalytic Converter FAQ

 

A non carb compliant catalytic converter will still work, the check engine light will turn off. It's just not legal to use that part in CA

 

Good to know. Thanks!

 

For what, an extra $100 or so, you can keep it stock, avoid possible gotchas, AND keep the air cleaner?

Meh.

 

Can you tell me if what converter you used for your replacement and if you passed your emission's test? I only have 10 days to get mine fixed or I'll not be able to renew my plates in Illinois. I've been out of town for the past 3 weeks and almost all year with medical issues so I was shocked to see the reminder that I needed the emissions test done by the end of the month. I have a Prius that says California on the sticker and I can't afford to get this wrong. I need the car because of the medical issues going on and I really don't have the money to mess it up. Illinois does not have CARB testing but the car sticker says CAL so if I put a non factory replacement on the car will the codes and light reset and pass or will I still be in trouble? I have a 2008 Prius with about 135000 miles. Unfortunately the family medical issues have been first on the list so the service engine light has been on for several months. Can you give me any solid advice? I don't even know if I am writing this question properly in this forum. Thank you for any help.

 

What needs welding?

Maybe I'm missing something and need to watch some more videos. From my grossly inadequate review regarding this matter, appears two bolts with springs and a gasket on the manifold and press fit and clamp on the tailpipe end. I'm looking at the eBay and Amazon direct fit ~$60 to ~$110 ones.

I'm getting ~30 to ~38mpg as well. How much mpg improvement should I expect to see once the above cat and Denso sensors are replaced and assuming those P0031, P0037 and P2238 codes reset and don't re-appear?

 

The cat they are talking about is not direct fit, not the same as the one you are looking at on Amazon.

Google Magnaflow 99205HM Universal Catalytic Converter (Non CARB compliant)

 

Makes sense, though I read literally as: "In both cases, the installation is about $200, because it needs at least welding job on one side."

 

I wound up investing in the "Catalytic Converter for 2004 2005 2006 2007 2008 2009 Toyota Prius 1.5L" AutoShack one for $67.54 delivered for and taxed for $71.59. https://www.ebay.com/itm/352894459085

For the downstream O2 sensor, I installed a new "Denso 234-4623 Downstream Oxygen Sensor with 23” 4-Wire Square Plug Harness for Calif. Equip"

Now I only have the P0031 and P2238 AF related codes, though the monitoring appears to be incomplete for a few tests where the P2238 is listed as Pending only.

I was actually surprised from what I read regarding the donuts, where my I guess OEM manifold to "custom exhaust" pipe was trashed. Though the rear donut was in good condition from the donor yard car. So I used what came with the cat for the manifold donut and went to Autozone to get a 1-3/4" stainless steel exhaust pipe clamp since the one that came with seemed a bit large. Amazingly, and to my total surprise, I felt no exhaust leaks from any of the seams I could get my hand around.

Now, I hear my engine making noises and significantly less exhaust sound. Seems to feel a little smoother on the acceleration as well and not vibrating like I've noticed before when starting.

Since my drivers side HID is doing the "flickering and not working erratically" thing, I decided not to drive anymore until the next day. On another note, I scored a pair of Halogen headlight assemblies on the last 50% of sale at the yard along with some bulbs with connectors that look good enough and will swap those in when I get the time.

First things first, getting rid of the trouble lights and codes.