BEGI Off-Road Pipe on the way!

Yes, it bolted right up. No CEL from removing the 1st cat. I just received the same code that I always received since installing the Turbo...P0421. Be sure to get a new graphite ring gasket. Nothing like trying to install the pipe on the weekend, and realizing that you need a new one, but the stealerships's service departments are closed.:mad: This happened to me, so I had to substitute one from GM that I got from AutoZone. 2 1/2 inch.
 
Isn't P0421 a Cat malfunction code?
I would assume that would be the code thrown when the cat is removed.
 
Woudn't you have to get the catco between the O2 sensors or they will still trip out?
 
1st MP3 in NH said:
Woudn't you have to get the catco between the O2 sensors or they will still trip out?

my belief in a start to taking care of this 02 problem is this. the first o2 you should try and mount in the exhaust manifold. yes i said manifold, before the turbo. where EGT's are greatest. to give the ecu a VOLTAGE comparison. ill explain in a minute.
then the second o2 AFTER the second cat.

you see the mazda ecu " monitors" cat efficiency. i posted about this earlier but some did not get it. the ones that did did not take it to heart.
now if you can show a larger voltage differential between the two sensors the ecu will think the primary cat is still in the vehicle and think it is working just fine and dandy.!:D

if anyone still does not believe this please read this thourally . at some point on the page you will see the o2 section and youll see what im talking about.

http://www.asc50.org/OBD-II Reference Guide Mazda.htm
 
1st MP3 in NH said:
Isn't P0421 a Cat malfunction code?
I would assume that would be the code thrown when the cat is removed.

It could also be an exhaust leak too. I started geting this code after the turbo install, with my 1st cat still in.
 
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Umm. . .hello? You rang?

Also, is everyone just getting their codes read at Auto Zone or something? I really ought to do that, but I end up unplugging the battery so often (other issues) that I reset the computer and the CEL is gone (for a couple days). Mine takes some time to throw it. Not sure what it is doing.
 
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