Can anyone provide steps and possibly pictures?


Tks,


Bob

 

Correct me if I'm wrong but doesn't a 2k max have a cat in the y pipe and not pre- cats as the 5.5 gen on does?

 

As far as I know, some 2k's, like my California Spec, have 2 pre-cats, just like the 5.5 gens. Federal Specs have only one pre-cat.
To the OP, I'm not sure if there's any How-to for the pre-cats in these forums.

 

Lol me= fail I didn't even think of the Cali spec..

 

What makes you think the pre-cats need replacing? Throwing a code?

 

Not sure, but make sure you are in need of pre-cats before replacing them. They aren't cheap...

You can replace your rear pre-cat with an aftermarket y-pipe which removes the cat in the process. It should not give you an SES code, and you should still pass smog just fine as long as the car is warm prior to smogging.

The front pre-cat is different and will throw a code if you eliminate it, I believe P0420 or P0430 (one of these is front bank and other is rear bank). If you are replacing the rear with a y-pipe the front is easy, just have to remove three bolts and you will have it off.

The y-pipe removal and installation is pretty straight-forward as you remove it from the bolts on the exhaust you see just below the car and then you have three bolts up top which will take a long socket extension to reach. I would suggest using wobble extensions or angle extensions to get to them.

Still...be sure you have to replace them before taking on the task.

 

To replace the bank one cat, must you replace the whole y-pipe or can you chop out the bad cat and weld in a new one?

 

Usually when the topic comes up folks are gutting them, not replacing them; I don't think I've seen info on that around any Nissan forums.

 

Gutting it is the cheapest way. This pre-cat is not needed by the car, except for warming up. It shouldn't throw a code if you do this.

The alternative is to purchase an aftermarket Y-pipe. You can even get some performance gains out of an aftermarket Y-pipe.