P0420?? Need help.
 

Okay. Here's the deal. I've been battling a check emission code, P0420, for a while now. I've done my research. I'm familiar with what the code is. I've already changed the post cat O2 sensor (rear). And yet, I still get the code. I can only assume that my cat is bad. My question is will/can the TL-S oem converter, Part#18290-RYE-A00, substitute for the oem rl converter, part #18290-RJA-A00. There is a $200 price difference.

Thanks in advance...

save yourself a bunch of $$$ plus gain a couple hp and get a straight pipe ($50?) and an 02 simulator ($80)

You may want to try checking the harness to the o2 sensor. I had a similar problem on my CL. I ended up changing the sensor and checking every fuse. In the end it was a simple adjustment of harness and a reset of the ecu. It may save you some cash.

if you do that your exhust will smell and o2 sim i dont think i would use one on this car. It may be just a diffrent flange on the tl-s . i havent looked but is there not 2 o2 sensors?

Yes there are 2 o2 sensors... However, the fault code refers to the post cat sensor.. Are your certain that the flange is different on the TL-S converter?

Okay. I finally got around to addressing this "P0420" code. After speaking with a Acura tech, I now have a full understanding of what's going on. The P0420 code refers to the "primary catalytic converter". Which is located in the rear (firewall side-Bank 1) and a P0430 code refers to "bank 2" which is in the front. The tech also told me that the P0420-P0430 codes are some of the most accurate codes our cars produce. I started to experience catastrophic gas mileage... I mean 10-12mpg.. (Yeah... It was that serious) But I knew something had to be done once the car started to get sluggish...

So on to my findings. I originally started this post inquiring about the TL Type S converter, If it was interchangeable with our vehicles. And the answer is YES. I did the work myself and the car runs like a dream. Gas mileage is back to normal and the code is GONE!... Why is this important info? Because there is a substantial price difference between our (RL) converter and the TL Type S converter.... They are exactly the same part, but with different part #'s.... So to current and future RL owners who has or will get a P0420/P0430 code, you can order the part yourself and bring it to a mechanic of your choice and save $500-$1000....

oh nice thanks for the update!

18190-rja-a00, 18190-rye-a00, 18910-rca-a00.
 

well i did a little more research and found out that part #
18190-rja-a00, 18190-rye-a00, & 18910-rca-a00 are the same and it gets cheaper from RL, TL, and V6 Accord.

Honda does this to make more money from people who have more expensive cars. RL parts cost $648-60 core, TL cost 550-60 core and accord is 380-60 core. What a Difference!!!!!!!!

Great thread, thanks for circling back.

V6 Accord cats have a higher cell count and are not as free flowing as the RL and TLS cats. V6 Accord and TL-P cats are 900 cell while the TLS-RL cats are 600 cell. So no they are not the same part as they have different internals.

Only cats that are the same are v6 Accord 03-07 & TL-p 04-08 (900 cell count) as well as 05-08 RL 07-08 TLS (600 cell count) but they ALL fit the engine block which is why we can use Richie's (RV6) HFPC and PCDs

im gonna do an RV6 HFPC on my '07 ody

You should, the 3.5 is ripe for it. :thumbsup:

Great find on the TL-S converter, but from experience when you get p0420 cat code, there's also a $4 fix that you can do and thats to get a spark plug defouler. You'll have to drill it so its big enough to fit into your o2 sensor, mount it on the sensor then mount it back on the cat, and bam cel gone and car runs normal:2cents:

Thought it meant "stop driving, you're stoned" lol