Catalytic converter help!!!

[Rozay_LS]

So I read that if I run bad spark plugs and ignition coils that eventually my catalytic converter will kill out, well I think that is what is happening now or at least starting to , my question is what is the risk or if there is even a risk cutting the catalytic converter out and just running my dual straight pipes with out a resonator or catalytic converter ? Will it destroy my engine ? Is there something I need to change to make that work ?...

 

[1LoudLS]

cutting the cats and resonators out will give you two side effects. First, not having properly working cats will produce a Check Engine Light (CEL). Second, not having cats and not having resonators will cause your exhaust to be louder.


the only "risk" you would be taking (not counting any legal ramifications modifications like that could bring) would be to miss while cutting and cut through your floor or something else.


removing your cats will not destroy your engine.

 

[Rozay_LS]

I cut the resonator off and just have my cat and straight pipes rite now , so would you say don't cut the cat off and I will be fine or just replace it and if replace it , with which brand or do you have a good website for parts for Lincoln LS

 

[sacsfin3st]

I cut the resonator off and just have my cat and straight pipes rite now , so would you say don't cut the cat off and I will be fine or just replace it and if replace it , with which brand or do you have a good website for parts for Lincoln LS

The cats are dealer only here in Cali. Not sure if this is the case elsewhere. Also, expect $1200/cat from the dealer.

 

[Rozay_LS]

Yeah I'm in Kansas so it is different here , what do you have on your car now

 

[1LoudLS]

so would you say don't cut the cat off and I will be fine or just replace it and if replace it

well if your cats get too bad, they will be clogged up and the motor wont run, so...


either replacing or removing the cats will be your only option.






however, if you replace your cats, make sure you fix what damaged the cats originally first.

 

[Rozay_LS]

If it was your car would you replace or run no cats

 

[Telco]

If you want to run catless you'll need to program the rear O2s out, or you can try the spark plug antifouler trick. You get Help! spark plug antifoulers that have the same thread size as the rear O2s, drill the small hole out to the same size as the inner diameter of the pipe, screw the antifouler into the rear O2 port, then screw the rear O2 into the antifouler. If this doesn't clear the CEL, use a second antifouler screwed into the first one. If that doesn't work then reprogramming is the only option to clear the CEL and run catless.

If you decide to replace, I've had good luck with Dynomax universal cats from Summit in the past although I have heard of folks having problems with them.

I run cats on my vehicles.

 

[Rozay_LS]

When you say rear o2 you mean the O2 sensors ? And what if I don't reprogram it and just leave it like it is with just the straight pipes and have it redone later like you mentioned ?

 

[LS4me]

The engine was designed to use information from the O2 sensors to regulate the mixture. Without that information the computer will use a default setting. You may or may not be running lean or rich. In any case, your mileage will probably suffer. Catalytic converters aren't the bottle-neck they were when they were first introduced; they, in fact, flow pretty freely these days. Rock Auto has them for less than $240.

Personally, I would never run a computer controlled system without the appropriate sensors. On the other hand, my '65 Mustang did just fine bypassing the added on emissions crap as the engine wasn't designed for it.

 

[1LoudLS]

When you say rear o2 you mean the O2 sensors ?

specifically the rear pair (the LS has 4 total)

 

[MIdad]

The engine was designed to use information from the O2 sensors to regulate the mixture. Without that information the computer will use a default setting. You may or may not be running lean or rich. In any case, your mileage will probably suffer. Catalytic converters aren't the bottle-neck they were when they were first introduced; they, in fact, flow pretty freely these days. Rock Auto has them for less than $240.

Personally, I would never run a computer controlled system without the appropriate sensors. On the other hand, my '65 Mustang did just fine bypassing the added on emissions crap as the engine wasn't designed for it.

The only function of the rear o2 sensors is to monitor catalytic efficiency, running with anti-foulers or Mil eliminators will have no effect on gas mileage. They can be bought if you do not feel comfortable making them yourself here: http://www.latemodelrestoration.com...tang-SVE-Mil-Eliminators-O2-Sensor-Simulators or you can follow the schematic in the picture.

 

[hite337]

I would replace my CATS. They are not that restrictive. I have tried aftermarket Thunderbolt hi-flow CATS and the CEL came on often. I replaced those with Eastern CATS and my LS runs so much better. The Eastern are OEM form fit and function.

 

[jjcool00]

I'm using the magnaflow cats and some other members are as well and I would report the same findings as Hite, excellent performance and sound.

 

[hite337]

I have heard good things about the Magnaflow CATS, but I have never tried them.

 

[Rozay_LS]

Thanks guys, so here is my plan for next Friday change the spark plugs and coils and then cut the cat out and install 2 rear O2 sensors in the back and I should be good to go ? Is it possible to change the O2 sensors at another time ?

 

[MIdad]

Check your private messages rozay. You will get a check engine light if you remove the cats and do not use some sort of mil elimination technique. personally I prefer the mil eliminators over the antifoulers. I would not replace the downstream O2 sensors until after you remove everything and install the mil eliminators or the antifoulers. Why do you think the downstream sensors need to be replaced?

 

[hite337]

Eastern CATS Part numbers:
Right #30410
Left #30409

Rockauto.com has the set for less than $400 shipped.

 

[Telco]

Check your private messages rozay. You will get a check engine light if you remove the cats and do not use some sort of mil elimination technique. personally I prefer the mil eliminators over the antifoulers. I would not replace the downstream O2 sensors until after you remove everything and install the mil eliminators or the antifoulers. Why do you think the downstream sensors need to be replaced?

Didn't know anyone was willing to post up the schematics for the rear O2 eliminators. They would be the better way to go as the antifoulers MAY, but are not guaranteed to work.

Most folks think that the rear O2s setting a code means the sensor is damaged, but sometimes they throw a code because they are doing their job and reporting a defective cat.

It's also not necessarily true that the rear O2 sensors are only there to monitor the cats. I've heard that on the newer vehicles they are starting to use the rear O2 sensors for mixture fine-tuning. I doubt the LS is new enough to be using this, but wanted to mention that the old thinking is soon to be just that, old.

On the Magnaflow cats, currently running a single 3 inch high performance cat on my Silverado, works great. No idea if it would set a code though, as I have the rear O2s turned off.