Does anybody have a Warpspeed Y-Pipe, Magnaflow (MF) High-flow cat, and that nagging P0420 code?

Over the past year, the P0420 code seems to return about once a month.
I'm growing very tired of resetting it. I'm afraid of wearing out the OBDII plug from all of the resets. Ha!

So tonight I received a new Weapon-R. It may be a couple of weeks before I get to install it. The weather is really crummy right now.

The Weapon-R instructions say it will not work if a cat is still in the exhaust system with the vehicle. I don't think I have much of a cat or I wouldn't be receiving the P0420.

Has anybody with my combination of WS-Y + MF HFC & P0420 found a solution with the Weapon-R?

Here's a picture of the Weapon-R.

 

Not a 4th gen in my case but I used an elbow exactly like that in my 02 Maxima for a secondary o2 sensor when I installed my headers. So far no codes after almost 2k miles. Good luck keeping that code away.

 

I had the same problem with that high flow magnaflow CAT. The O2 spacer only kept the P0420 from appearing as often.

Read these threads I posted in regarding that setup.

https://maxima.org/forums/4th-genera...ing-p0420.html

Post 153

https://maxima.org/forums/4th-genera...ll-pics-4.html

 

Thanks JH. I remember those threads about the generic cat. I actually have two OEM cats available to put on this one. One is in better condition than the other. I will need to pull the one in better condition from the donor car.

Did you need to remove the S-pipe to install the Weapon-R elbow when you tried it?

 

I didn't have to drop the extended b-pipe to install that elbow. With an extended BOSAL B-pipe I no longer have that intermediate pipe.

 

The OEM CAT lasted 6 more years after reinstalling it for that defective HFC made for Buicks.

 

Good to know JH. Thank you.

 

How long have you had the Magnaflow cat? All cats are required by law to have a 2-year/25k warranty (in California, it's 5yr/50k)

I've had good experience with Walker and Eastern cats.

 

As stated in the thread I attached they won't warranty a CAT installed on our A32s because it's made for a Buick.

 

I've had it about 3 years. The last year has seen a lot of P0420s.

My youngest son called and said he has fixed this issue on his Civic (with headers and deleted cats) and on a friend's catless Ranger/Danger pickup with a 5.0 V8. They put together some combination of a spark plug extender and another part that sounded like the Weapon-R elbow to trick the rear O2 into thinking everything is ok. He'll be back from school next week. I'll get him to figure it out. Max III was his car before he took over the Civic.

 

I had the same Problem! po420 kept popping up, new cat, y pipe. Emission parts new. Only way i resolved it was by putting in 95 ecu, code never came back.