i am thinking about to buy a cattman-y-pipe $350.00 for my 2000 max SE (california spec).cus i saw some post about wrapspeed suck.I think my pre-cat is not function since i got the DTC code P0420&P0430 and already update the ECM from dealer and the code came back again. Do u guys think if i get a cattman-y-pipe will slove the error code problem or still remain? and the cattman-y-pipe fitment good or not,or does it make any loud noise??? any suggestion?

 

Cattman fits great, no problems. And no it will not solve your O2 issue. You need to get the O2 sensors fixed. If your car isn't detecting 4 working O2 sensors, then the light wont turn off. You can re-route the O2 sensors if you want, but you need all four to be in working shape.

 

but the dealer said it's not the 02 sensors problem. cus p0420&p0430 doesn't say oxygen sensors...they told me to replace 2 precat...any idea?? cus i just want my SES light off and don't wanna spend 1000 dollars to get the cat from the dealer...not really interested in performace...hehe

 

Ah, sorry. Misread it:

P0420 Catalyst System Efficiency Below Threshold (Bank 1)
P0430 Catalyst System Efficiency Below Threshold (Bank 2)

Well, I guess a Y-pipe would cure the problem since it requires the removal of pre-cats. So yeah, look into that.

 

I may very well be wrong, but I was under the impression that the Cattman Y only replaces one of the pre-cats... He would have to go with headers to get rid of both..

 

Cali spec cars have a precat in the front manifold, then precat in the Ypipe and main cat under the car downstream from the Ypipe- between the Bpipe and Ypipe basically. P0420 code would be eliminated since the Cattman Cali spec Ypipe moves the O2 sensor from behind the Ypipe precat- up front so it reads the cat working on the front exhaust manifold- P0430 indicates that this cat is not working eighter. In this case you need to order up a set of headers- cause the cats are most likely gonna cause a restriction if they are not working, and then get www.o2simulator.com that basically tricks the ECU into thinking the cats are there and working fine. This little Simulator would work on your car with stock or Cattman Ypipe, but that front manifold cat could really be clogged. And this will hinder the performance of your car, worst case scenario is the cat will start to fall apart and engine will suck up particles of the cat durring engine deceleration causing cylinder wall and piston ring damage. Nissan has issued a recall on the Sentra SE-R and Altima with the QR25DE 2.5L 4 cylinder engine for problematic cats, which would fall apart and get sucked into the engine. This was a big issue with these cars, and alot of them ended up burning oil like crazy due to cats killing the rings on the pistons and scoring up the cylinder walls in the engine. When my front cat started to go- I could tell by seeing silverish flakes of ceramic substance on the outside of the cat, which lead me to belive something was wrong. I took the cat off and noticed it was falln apart, so I gutted it and then later on repleaced it with headers. Sorry for the confusing post.

 

that's really confuse me..hehe..so if i get a cattman y-pipe that will hinder the performance of my car....and i gotta order a set of headers to slove the P0430 problem? so the Y-pipe doesn't include the part of front pre-cat( bank 2)?

 

The Y-pipe eliminates the rear pre cat on a cali spec Max. The O2 sensors plug into the Y-Pipe, so if the O2 sensor is bad, I wouldn't think that your problem would be solved. I could be wrong ...

 

If the 02 sensors are bad- Ypipe will not solve your problems with the codes, if the front cat is bad - one in the front manifold, the check engine light will still be ON- cause the 02 sensors- if good, will say cat is not good. So what you need is some 02 simlulators to make the ECU think the 02s are good and so is the cat- and Ypipe will gain you HP and make your car faster, but not as fast or powerfull as a set of good headers like HS or Cattmans.

 

why don't you spend a little bite more to have Cattman Header, which including the Y-pipe. U can't buy a header alone anywhere.