So, as i mentioned in a previous thread, one or both my precats are dead. Since i spent all my money buying my kids lumps of coal for Christmas (its cheaper if you buy coal by the bag), headers aren't an option so my present to myself is to get my 2k2 running so I can keep driving to work.

I did some searching, and was wondering whats the easiest way to do this?

option 1: remove y-pipe and have at it with a chisel and hammer? I can see how the rear precat is accessible, but the front one has a curved length of pipe following it so the element may not be accessible from below?

option 2: remove y-pipe and drop front precat? is it possible to reach all the bolts that hold it to the manifold from above? it looks like a major pain in the *** to do this. (as seen in this pic below - sorry to the original poster, had to borrow your pic)



Also, whats the consensus on the best way to remove the actual element? Power drill? dremel with cutting wheel? firecrackers? .357?

Any tips that will save me hours of cursing, bleeding, and gesticulating?


thanks in advance!

You can remove both precats pretty easily once the Y-pipe is out. The material inside will be very brittle. It will break apart and come out pretty easily with a screw driver.

Be sure and wear eye protection and a mask to avoid breathing the dust.

Hopefully you are not in a state with emissions testing, because you will fail and be fined.

Not necessarily, as long as his main converter is still functioning properly.

that entire precat comes off of the header, if you do that it should be very easy to gut it. but then you still have the rear precat to deal with which will be more of a pain in the a$$


this is what it should look like once it is sepperated and as you can see it is easy to gut from this point
http://info.rockauto.com/EasternCat/...html?40387.jpg

They say he can punch out cats from a million miles away.

Sorry couldn't resist.

All information above is correct, all precats are good for are for cold starts once the car has warmed up the main cat takes over for emissions.

Ah!

thanks for all the help folks. Yes, the idea is to warm up the main cat to pass smog. Failing that, there's always a few ounces of alcohol in the gas to help things along.

I'm going to try to drop the front cat but hollow the rear one while it's on the manifold. It'll be nice to get some performance back.

You may as well drop them both. Working under the car with that stuff falling in your face is going to be a lot more hassle than removing a few bolts.

You'll also need an o2 simulator to fool the computer into thinking the cats are still there. If not the car will rat you out with a CEL and you won't pass inspection. Sometimes it takes a week or so to triger but it will eventually. It may show up when they plug into your OBD2 port even if there's no CEL showing.

The simulator is pretty simple and easy to hide. You'll need this one with dual output. http://www.o2simulator.com/index.php...products_id=10

But i thought you didnt need the o2 sim if you got a cattman y pipe though

I have a warpspeed y so my rear cat is gone but i still have my front and i havent gotten any codes from it...

Piece of open pipe/tubing with an outer diamater of an inch or so works great w/ a hammer.

The 02/03 cars are different. There are 4 o2 sensors. The front sensors are there to tell the computer how to adjust the ARF. The rear sensors are only there to tell if the precats are working properly.

The 00/01 cars have an o2 after the main cat. The 02/03 cars don't have anything after the main cat so that can go away without any simulator.

Ehh? My '00 Cali Spec has no O2 sensors on any of the tailpipe after the main catalytic converter. All O2 sensors on that car (and my '00 GXE Cali Spec) are located before the main cat.

any ideas about power gains from this?

there are power gains from adding a y pipe to the 00-01, because its attatched directly to the piping itself, where as with the 02-03, adding a y pipe only adds MINIMAL gains

Ok, i'm pretty much stuck. Front precat went nice and smooth.

Rear one, the element is melted. Tried removing the element while on the car with a drill and some mean looking bits, also tried chisel and hammer.. that stuff is almost impossible to remove.

Then tried to drop the rear cat. top two bolts were a ***** to take out because the heatshield got in the way and was itself hard to remove. Then went to crack the bottom bolts.. even after soaking in penetrating spray, they were stuck. I broke 2 sockets and 2 extensions trying to get them out.

So I'm pretty much stuck. Going to tow it to a mechanic today to finish the job. Sigh.

Good luck trying to find a shop that won't have a problem removing emissions equipment, especially gutting a converter.

Be careful taking it to a shop. In some states they're required to report someone trying to remove emissions equipment. In all states the shop faces a very stiff fine for removing a cat. If they don't know you really well they probably won't do it.

I would suggest finding someone who can help you at your house. Maybe someone from the Org. If not, invest in some stronger tools and try it again.

Yeah, the Cali spec cars are like the 02/03 cars. Forgot about that.

I would try it but.... When you do it!... Get yourself a dual O2 simulator and make sure when you remove the catalyst you don't leave any material (catalyst) hanging in the exhaust airstream. It will disrupt your airflow negatively. It best you remove all the material, you should be able to split the manifold from the catalyst!

Exactly right. If you don't get it all out it will end up in your main cat and cause problems there.