Replacing cats and possibly o2's - advice

[Pancake81]

Hey team,

I got a 2002 supercharged X with about 320,000 km on it. My cats have been pooched for a while and I would like to replace them. Trouble is, Nissan wants about $2000 to replace them. Which honestly is about what my entire truck is worth. I have heard aftermarket cats just don't hold up.

What are my options here, are there any good ones? I have no air requirements to meet, I could care less if I have any cats. But will my x run smooth without them? Would it require a re program?

Any advice appreciated

 

[granitex]

Get a set of thorley long tube headers, it will eliminate the first set of cats, CEL's will keep the check engine light off, and if the secondary cats are bad also a test pipe to bypass them can also be done. The performance improvement is worth it even if the cats were still good.

 

[KBC]

I'm in BC as well. I just replaced the entire exhaust on my 2001 other than the headers I put in 1.5 years ago. I put cheap aftermarket cats in for the secondary ones at the same time as the headers and they were junk.
Does your exhaust bolt together with flanges or is it sleeved?
2000 Xterras only had primary cats and the pipes from that year were a direct bolt in to replace my secondary cats in my 2001.
I noticed an improvement in power mostly on the highway with just the headers and as of this past Sunday when I took the cats out and put a Gibson performance cat-back exhaust in I noticed another improvement in power. I'm not sold on the way it sounds though...
No re-program or CEL eliminators used. I went the cheap route and used a pair of spark plug non-foulers on each rear O2 sensor. All you have to do is drill one out to 1/2", thread it on to your sensor, and then thread the un-drilled one on and install it on each side.
Where are you located? I'm currently living in Abbotsford but work in Langley if you want to take a look.

 

[Pancake81]

Get a set of thorley long tube headers, it will eliminate the first set of cats, CEL's will keep the check engine light off, and if the secondary cats are bad also a test pipe to bypass them can also be done. The performance improvement is worth it even if the cats were still good.

Okay, so I can order up a set of the Doug thorley long tubes and bypass the first set. What's this about a test pipe?

 

[Pancake81]

I'm in BC as well. I just replaced the entire exhaust on my 2001 other than the headers I put in 1.5 years ago. I put cheap aftermarket cats in for the secondary ones at the same time as the headers and they were junk.
Does your exhaust bolt together with flanges or is it sleeved?
2000 Xterras only had primary cats and the pipes from that year were a direct bolt in to replace my secondary cats in my 2001.
I noticed an improvement in power mostly on the highway with just the headers and as of this past Sunday when I took the cats out and put a Gibson performance cat-back exhaust in I noticed another improvement in power. I'm not sold on the way it sounds though...
No re-program or CEL eliminators used. I went the cheap route and used a pair of spark plug non-foulers on each rear O2 sensor. All you have to do is drill one out to 1/2", thread it on to your sensor, and then thread the un-drilled one on and install it on each side.
Where are you located? I'm currently living in Abbotsford but work in Langley if you want to take a look.

Thanks for the advice. I am in Prince George, so be difficult to swing by. Appreciate the offer though. To be honest, I would have a shop perform the job for me, due to time and lack of welder. I think I will go the DT header route to eliminate the first ones, but curious about the second ones and O2 sensors. Tell me a bit more about this spark plug option, can I purchase these somewhere?

You mentioned you replaced with aftermarket cats in the second ones, but they were junk. Did you just eliminate them all together then?

I don't care if I have none, but worries the ECU will start going nuts with air fuel mixture etc. don't want my x running like junk, but also don't want my engine sucking in bits of cat. Oh, and I don't want to sown a few grand lol. $600 on headers and some exhaust work is reasonable. Just want a plan before I walk I somewhere and get taken for a ride

 

[granitex]

you have two sets of cats, primary and secondary, the primary cars are attached to the manafold,the secondary cats are further down stream. the test oioe would replace rge secondary cats

 

[Pancake81]

Okay, that's what I was hoping to get clarified. So the headers will eliminate the first set, and the rest pipe wil eliminate the second set. Leaving me, no sets, lol. So it's all good to remove all cats, and the vehicle will function good?

 

[granitex]

it will, youo just need to account for the o2 sensors, it does dictate how the ECU manages things.

 

[Muadeeb]

you have two sets of cats, primary and secondary, the primary cars are attached to the manifold, the secondary cats are further down stream. the test pipe would replace the secondary cats

Not all models had the 2nd set of cats. I guess there were a few dogs in the factory that day (groaner is groan worthy). But, yeah. Thorleys, CELs, and a shop to custom up the exhaust is the best way to go.

A CEL moves the O2 sensor out of the exhaust pipe, so less gasses get to it and makes the computer think the vehicle is running cleaner than it is. Typically, we go with 90* ones (like this: http://www.amazon.com/Degree-Angled...qid=1460638137&sr=1-1&keywords=cel+eliminator) because it gets a bit tight between the body and the exhaust, but if you have a BL, then a drilled out spark plug nonfouler will work too. I've used that trick on a different vehicle before.

 

[KBC]

Unfortunately with the Canadian dollar where it is right now you are probably going to spend $600 just to get the headers, never mind any labour to put them in.
I did eliminate all of the cats.

 

[Pancake81]

Yeah, you are bang in with dollar. Headers will run me about $700 after shipping with the exchange rate. Plus a few hundred for Nissan to throw them on. I checked out the check engine light eliminates, should work like a a good thing. How many will I need, and where will they need to be installed (I am assuming between the O2 sensors?

If I bring those to a shop will they know what they are/how to install?

 

[Muadeeb]

Front sensor will go in the header like normal. Eliminators get screwed in where the rear ones go, then screw the sensor into it

 

[granitex]

The labor is free, something that you just have to suck up and do yourself, nothing more than nuts and bolts, and getting into tight spaces. No need to pay factory shop rates for something that you can do in your driveway.

Not a better way to get your man card punched than doing your own work.

Starts to justify stuff like facial hair and flannel shirts.

 

[Pancake81]

Yeah I hear ya man, if I had the time I would. But reality is this is still my daily driver, I have a demanding career with little time off, and a new born and wife that absorb the remainder of it. It's not that the job is too difficult, it's that people are saying with no body lift its a 6-8 hour shop job. So roughly 10-12 hours for me. Can't afford to not have the job finished and a usable vehicle at the end of a day.

If I hold off until I use some vacation time it's a possibility. But I assure you, it's not laziness

 

[granitex]

no worries just a little nut busting among friends.

 

[Pancake81]

Absolutely. I can handle the ball busting, but the situation is justified

 

[Pancake81]

When I pull the trigger I think I will order from 4x4 parts, doe to sale price. Is there anything else I should order for the install. Studs, bolts, gaskets?

 

[BEEFY]

I'm interested to see how your exhaust will turn out. I need to do this to mine as well. On a side note , good to see another Prince George xterra. If you need a had with anything on it I'm usually able to lend a hand.

 

[Prime]

When I pull the trigger I think I will order from 4x4 parts, doe to sale price. Is there anything else I should order for the install. Studs, bolts, gaskets?

Go over to Xterraperformance.Com get the same deal on the headers and actual customer service from people who really support us.

 

[Pancake81]

I would, but their international shipping seems to be an issue. They are definitely not the best price either, unless we receive a discount I am not familiar with

 

[Prime]

I would, but their international shipping seems to be an issue. They are definitely not the best price either, unless we receive a discount I am not familiar with

Hrmm. I bet if you put in a call or email to Dan or Chris @ Nisstec something could be done about that. It never hurts to ask.

 

[Pancake81]

Yeah for sure. I have to buy new rubber this week. So replinish the finds with a pay cheque or two and then do my serious homework. I am happy to support good sponsors.

Assuming the headers don't come with a new gasket, I will need to order one. Do you think I will need new studs, bolts, anything else...?

I hate when I order 90% of what I need. Then I have to sit and wait for the last part to show up

 

[Prime]

I would advise new Fel-Pro header gaskets, and a complete set of studs and nuts from the dealership. When taking the old headers off its likely that a few of the studs will come out as well. Also, on the back passenger side there are 4 locations for the studs around the exhaust port. But only two are used. The stock manifolds vs headers use opposite holes. So you have to remove those and flip them. Any time you remove a stud, you should replace with new.

You need an E10 external torx socket to remove the studs.