P0420 code??

[asianstyle]

autozone pulled the code and it said "the pcm has determined that the catalyst system efficiency for bank 1 is below threshold for the current engine operating conditions" where exactly is bank 1, b/c i need to replace the cat. converter and o2 sensor. does anyone have a picture or diagram for a 2001 max? I took it to the dealer but they want to charge me an arm and a leg for these two, so I'm gonna buy a high flow cat and o2 sensor from somewhere else and do it myself.

[MinisterofDOOM]

That one is in the exhaust manifold for the rear bank of the engine.

Since it is a crucial emissions device, it MAY still be covered under some sort of warranty.

[asianstyle]

can you show me what color sensor it is, I have a diagram link here. look at figure #3 on page 5. is it the black, blue, red, or white o2 sensor?? thanks man.

http://maxima.theowensfamily.c...a.pdf

[MinisterofDOOM]

It's the black one.

[asianstyle]

do you have any info on how to remove the catalytic converter?

[MinisterofDOOM]

Yeah, this article should help you out:

zerothread/215223



Also, a bit more research confirmed my earlier theory: the cats are covered under a federally mandated 8 year/80k mile warranty. There was a TSB for this problem as well.

[Beancooker]

Unfortunately, you will have to replace the front and rear bank precats, since they are welded together. If this can be fixed at the dealership for free, do it. This is a real PITA job, unless the weather is good.

[asianstyle]

beancooker, if I buy a aftermarket y-pipe for my 01 max, will it pass emissions since it will get rid of the pre-cat on my ride. just wondering before I purchase.

[Beancooker]

If you live in California, YOU WILL NOT PASS. The Y-pipe is what is called 49 state legal, good everywhere other than Cali.

BTW, your sig is way too big. I cropped and resized it for you.

[maxhopper]

Most all y-pipes come with a disclaimer that they are for "off road purposes only." This is because they eliminate emissions equipment (the precats).

Many people claim that given ample time for the car to warm up, you will be able to pass the tail pipe "sniffer" if your city does that test.

[asianstyle]

beancooker, thanks for cropping my sig. it was a little big. So are you sure about the emissions thing. just checking before i buy one. I was also wondering about this warspeed y-pipe that I found on ebay. Have you had any experience with these or heard of any. Looks the same as the stillen ones.

http://cgi.ebay.com/ebaymotors...ZWDVW

[maxhopper]

The only knock I have ever heard on the Warpspeed y-pipe is the they produce leaks in the flex section. The ebay deal you linked seems to be a killer deal for the y-pipe with a high-flow cat.

[jltibbs]

. . . if I buy a aftermarket y-pipe for my 01 max, will it pass emissions since it will get rid of the pre-cat on my ride. . .

i have headers (that came with y-pipe) and i passed. the hydrocarbons went from 9 to 86. thats not really relavent to you being that you have OBDII. as long as your CEL is fixed, you're fine. on the 'catalyst efficiency below threshold' code, most people that get that code replace the rear o2 sensor (behind the cat) or the cat itself. the only reason i have any knowledge of this is because i work for advance auto parts. the customers that do as i have stated says it fixed the problem, no more CEL. the actron diagnostic tool that we (AAP) and auto zone use is vague to say the least. about the only way to be sure whether or not it is the o2 or cat is to have a diagnostic test done at the stealership or a shop ($50 - $65). that's just to be safe. my recommendation would be the rear o2 located in the back side of the cat. good luck with it bro.

[asianstyle]

thanks for the info, what kind of y-pipe do you have? I'll get my car back from the dealer on monday. they wanted to charge me about $1400 to replace the cat and o2 sensor, so i'm gonna just buy the y-pipe and sensor from somewhere else. what do you think about the ebay warspeed y-pipe, maxhopper said that he's heard about the flex pipe producing leaks overtime. do you have any opinions?

[Beancooker]

I am running the Warpspeed Y-pipe. I have not had any problems with it. I've only had it on since summertime, so no leaks yet. I have no complaints about them, and think it's a decent quality product.

I'm not trying to be an arshole, and thank you for resizing, but sig pic size is 600 wide x 200 tall. The pic I resized is the Maximum size I could get for you. Feel free to use the properties of that pic, it's in my iServe resize folder, and will stay there. properties: http://is.rely.net/3-78-4172-l...A.jpg

[asianstyle]

hey beancooker, do you have the stainless steel or aluminized?

[jltibbs]

i have complete ebay headers. no exhaust leaks as of yet. if the price is right, go for it. the bosch part number for your rear o2 sensor is 13374 (AAP; it costs 95.48). if you're willing to make the trip to smyrna i can hook you up on the price. you can replace the o2 sensor in about 10-15 minutes if its like my 95. just let me know. [615.419.6962]

[asianstyle]

thanks jltibbs, I won't have time to come down to smyrna but thanks alot for the part number, i'll have to go to the one down the street from me and get it.

[Beancooker]

hey beancooker, do you have the stainless steel or aluminized?

Aluminized... Not making the under carriage show quality, so I saved the $$$ and bought the high flow cat too.

Here is the article that I wrote when I did mine. ARTICLE It's a really easy install. If you have any questions, or think you will, hit me up on AIM or email, and I'll give you my cell phone #.

BTW, thanks for fixing your sig

[asianstyle]

thanks for the help beancooker, I'll let you know. I went ahead and bought the warspeed y-pipe and high flow cat on ebay. I'll keep you updated. hopefully my check engine light will go off after installation.

[asianstyle]

what up beancooker, I've finally got my warspeed y-pipe in and high flow cat. I've had it for about a week now but hadn't had time to install it yet, but will this weekend. I had a couple of questions. I went to a muffler shop today to see how much it would cost for him to put this on, and he advised me not to do it b/c it would throw a code and that my check engine light would always be on. He said me getting rid of the precat would cause the check engine light to stay on and I asked him even if the o2 sensors are put back in it's original spot and he says yes. Is this true or will it be ok? Did you have any problems with yours after the install? did your check engine light come on? He said that it would be a job for him to do and I was thinking, it's just a few bolts and that's it. I don't think he knows what he's talking about, he said he's been doing this for fifteen years. one more question, did you have any problems with your bolts being rusted on, were they hard to get off, even after you sprayed them with loosening spray?

[maxhopper]

Your check engine light will not come on from eliminating the precats. When I intalled my y-pipe, the bolts going to the exhaust manifold weren't too bad, but I had to put a torch to the ones that connect to the main cat.

[Beancooker]

The mechanic is wrong. I never got a CEL, and I have the damned California emissions. You will eliminate the rear bank precat, but I never had an issue with a CEL, nor has anyone I've spoken with.

It took me about 2 hours, and that's because I was drinking and kicking it with my neighbor too.

Use some PB Blaster, and you'll be good to go. If no PB is available, any decent penetrating oil will work.