Catalic Converter Question.

[HyeLifeLS]

Hello fellas.

My question does not concern LSs but I just need some opinions.

I have a 99 Mercury Mystique V6. It has 127,000 miles on it and recently the CEL came on. Also, I did notice that the acceleration seams kind of bad, at least not as good as it used to be. I had a guy at the shop check the codes and he said that the CAT is dirty, I need a new one. I did call a muffler shop and they estimated $475 for a new one. That's kind of high.

My question is, if I remove the CAT and put a straight pipe instead (I know it's against the Smog regulations, but I don't wanna spend that much money on it right now) will it be safe for the engine? And what will the effects be? More power? Is it gonna make a lot of noise?

Thanks.

 

[HyeLifeLS]

Any ideas?

 

[5.7sbc]

You are correct, you will probably get more power and a louder tone but how it effects your vehicle will depend on the placement of your o2 sensors. O2 sensors tell the car how rich or lean the exhaust is, this in turn regulates fuel injected into engine. Also there is a fine for no cats here in MA I don't know if that applies in your situation. ($850 per cat missing) I would purchase an aftermarket high flow cat (they come in various diameters). They tend to be much much cheaper then stock check out ebay or call JEG's or Summit (they are universal fit) and then have a local shop weld them on for you. My brother was in a similar situation with his Yukon. Dealer wanted around 600 to replace the cat pipe. I found him an aftermarket one and we bolted it on in the driveway. No idiot light, no problems at all, better gas mileage and a better sounding exhaust. Oh, and we saved about 400 bucks.

 

[2001LS8Sport]

If you live in CA, the fine for removing your cat would pay for several of them....and....you will never pass the visual inspection. With that many miles, I would say the diagnosis is probably correct and it's time to invest in a new cat.

 

[SoonerLS]

I would be surprised if it ran correctly without a catalytic converter. I don't know the Mystique, but it'll either have one O2 sensor that screws into the cat itself, or one before and one after the cat. (My '95 SHO had O2 sensors that screwed directly into the cats; the LS has them upstream and downstream of the primary cats.) Either way, they won't be getting true readings, so the computer will be misadjusting the air-fuel ratio.

Just replace the cat...

 

[HyeLifeLS]

Thanks guys, I'll probably get one of the ones that 5.7sbc said.

Thanks.