Garrettz459

One of my friend helped me out check why I had a engine light came on again after replacing O2 sensor and the result was I needed a Catalytic Converter replacement.

I have a couple questions tho..

I was quoted with $390 for a replacement but how long can I drive with a broken converter? I was told it just a federal law for to pass emission inspection sticker and I'm still driving with a rejection sticker for almost a month!

I wanted to get a Magnaflow goes for about $65-125 avg compare to OEM $390 one...

So what would be the best ideal for me?

Thanks!

In a year or so I might have to consider getting a new car I've been getting allot problems in less 5 months. I will most def get Maxima again!

TallTom

A bad cat is a clogged exhaust = bad. Either replace it or gut it. Is it the main cat or a pre cat?

Garrettz459

It Pre cat

Child_uv_KoRn

iTrader: (7)

Read the threads. Do both ASAP (gut is better with O2 sim) or have fun with a blown motor.

If you're gonna replace those worthless things, then don't spend a dime more than you have to.

dcam0326

I suppose I can attest to what a clogged cat can do; I was getting off a highway exit when I noticed a lack of power. Managed to limp it to a friends house and had to get it towed from there. No blown motor, but I'm sure if I tried to push it it would've been bad news. Either way, gut that **** and get an o2 sensor if your inspection laws "allow" for it (i.e. no exhaust sniffing in your state, just straight up code reading).

Garrettz459

I'm pretty much a newbie about exhaust systems... what do you mean gut my pre-cat do you mean cutting it or replace it?

nestorlugo

iTrader: (11)

Gut'it like a fish! Take out the insides and put it back on...

colt149

iTrader: (1)

5th gen Maxima with VQ35DE engine:
: two precat : one near the radiator, Secondary Oxygen Sensor with red wire , one near the firewall , Secondary Oxygen Sensor with white wire.
: Main rear catalytic converter
: Two Primary Oxygen Sensor with blue wire: both near the exhaust manifold

Solution: gut the precat means, removal of mesh inside the precat and install it back, or remove the precat and install a header (OBX headers)
: Install a non-fouler to the two Secondary 02 sensor or O2 Sim
: Retain the main catalytic converter.

TallTom

gutting = removing the insides of the cat so it looks functional from the outside but is just a shell. You will need an o2 simulator or o2 nonfoulers to trick the ecu into thinking that it is fully functional. It's illegal to do so you will need to find a friend who is a friend who is a mechanic to do the work. It's cheaper than replacing the precats and you will get more power this way.

Itz Shak

Would you still get a code if you gut the precat? Also, what does it mean when you've had catalytic converter code and it goes away? I bought a catalytic converter for $170 and it's just sitting in my room for no reason now because the code came off. (If anyone would like to buy it ill sell it for $120 and that's negotiable. It's still in the box and all)

dwapenyi

iTrader: (3)

Do the issues of the 2002-03 maxima also apply to the OP's 2001 Maxima?

TallTom

If you gut the precat or install headers, you need to do something to the second set of o2 sensors that are after where the cats are/should be. You can install o2 simulators or attach nonfoulers to the ends of the second set of those o2 sensors which will trick the ecu into thinking everything is honky dory and not throw a code which is good for those of use in areas that have emissions inspections.

foodmanry

iTrader: (15)

Keep the cat...the engine codes P0420 and P0430 tend to come and go. As the cats continue to wear the codes come back longer and eventually stay on until you replace the cat/02 sensor.

foodmanry

iTrader: (15)

They are slightly different...both gens use similar exhaust setups, but the 2k2 and 2k3 seem to have more of an issue with the cats breaking apart on the inside and potentially causing damage to the engine. I haven't seen or heard of this on 2k and 2k1 Maximas.

NmexMAX

iTrader: (22)

02-03





01

Itz Shak

Gotcha, and will do. Thanks

boondoxmax

iTrader: (1)

Due to all the rust. It looks like it would be a PITA to remove and gut it. I figure I would just replace mine with a brand new aftermarket one. Maybe Eastern brand and replace the 02 sensor. From the look of mine, it looks like they will damn near half to destroy it just to remove it.

peb396

What are these nonfoulers and O2 sims and where do you get them?

RR5

iTrader: (6)

I had a p0430 I got after replacing an O2 sensor, maybe two. Replaced the cat and the code went away. Passed emission last year no trouble.

Itz Shak

Did you notice a difference mpg/performance wise after the replacement?

boondoxmax

iTrader: (1)

Which brand of cat did you buy???

ManualMaxima

iTrader: (10)

I replaced my front pre-cat around 2-years ago. It was a manufactured by BOSAL (purchased at autozone), haven't seen a CEL since...

RR5

iTrader: (6)

Didn't really keep an eye on MPG or performance, was simply trying to fix the problem.

Nissan OE, back (2010) then DaveB offered forum members a discount on Nissan parts.

Itz Shak

Understood

sanford7575

I think that Warpspeed makes an entire y pipe and hi flow cat set up for this gen. I would just swap it all out with new. I've never done an exhaust job where I didn't need heat, or I didn't need to cut something. I'm in Philly though, where salt and snow are a factor...

TallTom

The Warpspeed Y-pipe reliminates bank 1 precat for only the 2000 and 2001 maxima. You still will have the Bank 2 precat which I think is odd since it throws off the balance of the flow, but that's just my opinion.

http://www.warpspeedperformance.com/...ti_i30_exhaust