Hollowing out catalytic converter LS V8

[RigsLS]

Let's say .... hypothetically, that someone's catalytic converters fell off and the vehicle in question (for example let's say a 2001 LS V8 Sport) isn't worth putting new catalytics in to.

Now, assuming that our hypothetical vehicle owner lived in a state/province with emissions tests, like maybe somewhere in Canada, and was morally flexible enough to live with himself after intentionally disabling emissions equipment... how would this imaginary fellow go about fooling his 02 sensor into thinking everything was OK after he put straight pipe in where the cat was?

I searched around but couldn't find any threads, but I know that somebody in our grand family of miscreants must know the secret O2 trick. I have heard that you "zero out" the O2 sensors with a "jumper" of sorts, or even run a tune where they are zero'd out, fooling the ECM to think they are within tolerance.

I would ... errrr, I mean this hypothetical owner may or may not simply hollow out his CATS and leave the upstream sensors in and see if it throws a code.

Would be very interested in passing any information onto my imaginary friend with respect on zeroing out his o2 sensors.

Resistor Jumpers, Dummy o2 sensors, MIL eliminators ???

 

[1LoudLS]

if it was a mustang, you could order a set of harnesses in between the sensor and the cars harness, that will trick the car into thinking its working. at least enough to keep the light off. most of the time...

that's not going to be enough in they actually test the exhaust.

but then, this aint no mustang. and who knows if there is one like that that would work on this car...




I did have a diagram some where if what was in one, just not the time to go get some harness and try it.

 

[RigsLS]

Yeah, they don't do exhaust tail pipe sniff test here for emissions but rather simply plug into the OBDII port to determine all monitors are in valid READY state. Could easily be fooled.

I've seen ads for places like Jiffy Lube that will perform government certified emissions tests, where a 14yr old kid was 'trained' how to plug in a computer to read current conditions of sensors. 5 sensors require to be in a READY state around here, if a vehicle is prior to 96, 3 out of 5 have to be valid only. Exempt sorta speak.

There's gotta be something available for the LS V8 that simply snaps into the connectors.

I know I can .... I mean, my friend knows he can get his tune altered as well.

Would leave the UPSTREAM sensors in tact for F/A ratio balance but would like to eliminate the DOWNSTREAM o2's

 

[jgscott]

There is a company that's makes them for all cars. It goes in between the O2 sensor wire in the Cat. Its called a O2 Sims. But it fools the car but won't make it pass a Tailpipe Smog sniffer.

I think its just a resistor in a fancy box, weather proofed for under the car, but I don't know what resistance is need for the LS V8.

 

[Alax7]

You can get them disabled, Torrie should be able to do it. I don't know what the OBD2 reader will actually say when they connect it. I don't have O2 codes pop up.......

 

[G-RELL]

http://www.mikefordmustang.com/writeups/mil-eliminators/how-to-make-mil-eliminators.php

 

[izzy]

I bet if your friend goes to one of those places to have the testing for emissions done and give's one of those "qualified" dudes a handy out back. you.,....I mean your friend might be able to get a pass on emissions. :hump:

 

[Telco]

One thing your friend can try is spark plug antifoulers. Your local parts store should have them.

http://www.summitracing.com/parts/rnb-42002?seid=srese1&gclid=CPSCycuG7sYCFcQUHwodCyUCEA

What you do is get one, may need two, for each downstream sensor. Cut the very end of the tip off where the little hole is, which turns it into a tube. Install the antifouler into the O2 sensor hole, then install the downstream sensor into the antifouler. What it does is pull the O2 sensors out of the exhaust stream. There's enough exhaust passing over the sensor that the computer thinks it's reading the exhaust, but weak enough that it thinks it's reading catalyzed exhaust.

This is NOT guaranteed to work, but for the 10 bucks or so it costs it's worth a try. It's supposed to work reliably on some Japanese cars. You can look it up on the net before trying. Normally I don't agree with fudging sensor data because a fudged input equals a fudged output, but in the case of the downstream O2 sensor I have no problem with it.

A caution though - running with a hollowed out cat may cause the car to start smoking and stinking. The cats help burn off any oil smoke that might be caused by oil getting past the rings (not necessarily a problem until the oil leaks badly enough that the cat can't handle it), and any unburned fuel will also not get burned off. This means visible oil smoke and that fuel-y smell that pre-cat cars were known for.

 

[RigsLS]

http://www.mikefordmustang.com/writeups/mil-eliminators/how-to-make-mil-eliminators.php

Sweet! I'm getting the entire exhaust redone this Monday (today) gutting the partly clogged (right side) CATS (both) ... I'll see if I can affix this simple little problem solver to avoid the Downstream o2 out of range isssue. +1 too simple, I'll see if it works.

Errrr ... I mean my imaginary friend is getting all that done. Not me, I'd never do such thing, bad for the environment!

I bet if your friend goes to one of those places to have the testing for emissions done and give's one of those "qualified" dudes a handy out back. you.,....I mean your friend might be able to get a pass on emissions. :hump:

<looks up see if izzy owes him any favors>

cats help burn off any oil smoke that might be caused by oil getting past the rings (not necessarily a problem until the oil leaks badly enough that the cat can't handle it), and any unburned fuel will also not get burned off. This means visible oil smoke and that fuel-y smell that pre-cat cars were known for.

He said to tell ya, that's all good and all but it'll be a cold day in hell before he puts brand new expensive converters on his LS .... said, it'd see a river before it came to that.

 

[Telco]

Sweet! I'm getting the entire exhaust redone this Monday (today) gutting the partly clogged (right side) CATS (both) ... I'll see if I can affix this simple little problem solver to avoid the Downstream o2 out of range isssue. +1 too simple, I'll see if it works.

Errrr ... I mean my imaginary friend is getting all that done. Not me, I'd never do such thing, bad for the environment!








<looks up see if izzy owes him any favors>






He said to tell ya, that's all good and all but it'll be a cold day in hell before he puts brand new expensive converters on his LS .... said, it'd see a river before it came to that.

80 bucks each is expensive? I'd hate to make that little...

 

[1LoudLS]

80 bucks each is expensive? I'd hate to make that little...

you keep forgetting, this isnt a simple chevy...

super cheap cats are very unlikely to function properly (at least enough for this cars computer)

there have been a lot of people that had problem after installing cheap, or even not quite so cheap non OEM cats...

 

[RigsLS]

As the system was cut off and the inside of both CAT where blown out, car lowered onto the ground and a good few hard revs blew the remainder out.
Both Screens inside each CAT are in perfect condition after all, nothing was clogged up or deteriorated, a good blow out and it was decided to NOT gut them after all.

 

[RigsLS]

Nice symmetrical new system put back in place







Much cleaner job, just the tips turned out a little on the small side for me, will need to have them redone a bit.

At least the large chrome cannon tips are off.

 

[elephantrider]

looks fantastic ! this is on my "to do" list for the ls, here in the next few months.

 

[RigsLS]

80 bucks each is expensive?

Typical Telco again leaving the cap off the glue not understanding we'd be talking about actually putting the correct meant-for-this car OEM CATS on.

80 bucks OEM??? ok!

I'd hate to make that little...

Ugh, another sorry attempt of a poke of sorts to get me going again?

Telco ... I earn plenty me friend, just wasn't planning on spending large, if any on LS CATS.

 

[1LoudLS]

Telco ... I earn plenty me friend, just wasn't planning on spending large, if any on LS CATS.

cough cough 1600 cold hard clams cough

 

[jjcool00]

Looks good, guess I'm the only one that likes the loud drone

FYI - Still have Magnaflow cats on the car. No issues. Much cheaper than OEM too.

 

[Telco]

Yeah, I was poking the bear. You'd think a fanboi would have more of a "price no object" mentality towards their car . Poke poke...

And no, I didn't take that it was an LS into account although I wouldn't think that a universal 3 way cat would cause a problem on this car. Probably should have though.

 

[1LoudLS]

And no, I didn't take that it was an LS into account although I wouldn't think that a universal 3 way cat would cause a problem on this car. Probably should have though.

it seems the PCM in this car (and really a lot of real new cars) are just ultra picky in the range of good they will accept from the sensors... there have been more than a few times people have bought a "OEM like" set made specifically for the LS that has still thrown a code or two.

 

[1LoudLS]

Looks good, guess I'm the only one that likes the loud drone

while I'm not too crazy about a LOT of drone at cursing speeds, I do love me some seriously loud exhaust on acceleration, and I will put up with quite a bit of drone to get it! lol

honestly, when I had the Flomaster delta 44s and the resonator deletes on it, it sounded perfect to me... ever since the cats needed a little freeing up, then it has got a little bit too much, so I'm alway considering throwing another set of resonators back on. also been thinking I need to replace the cat chamber with some straight pipe since there is no more restrictive honeycomb needing the extra surface area of the enlarged cat...

 

[pragmatic]

The spark plug non-foulers should work if you put two on each rear O2 sensor. At least according to the posters on other sites (google "spark plug non fouler trick")

 

[elephantrider]

i tried the non foulers on my sons shytebox kia spetra and they didnt work. still threw a cat efficiency
code. i put a magnaflow header and high flow cat on it, and the rear o2 did NOT like it.

 

[RigsLS]

No clogged CATS after all, no MIL for the o2 upstream nor downstream BUT I did stay at a Holiday Inn last night where I discovered that Fn slight ticking noise is now confirmed busted secondary tentioners. My life! My life, I so love owning an LS in this life. <open wallet>

How much are Corolla's going for these day?