exhaust change question ??

[skooterbum]

hi guys, i have a 96 olds cutlass with the 3100 v6 with 107,000 miles on it. it is running bad right now and i am questioning the cat converter. my question to you is if there is a way to check the cats for blockage on the car or can i plan on cutting it off to check ?? if i have to remove it will i create performance probs for myself if i leave it off ?? also there are two oxy sensors on this. one right off the exhaust manifold and another after the cat. can i eliminate either of these or should i replace them both.
thanks
ron

[98malibu3.1]

If the cat is indeed blocked, it will have a bluish hue to it like when metal gets too hot and feel very sluggish. You should be throwing a code that says "Catalytic converter efficiency low" or something of the likes. DO NOT under any circumstance try to eliminate either the cat or the 2 O2 sensors. It will go into limp mode and really run like a turd. You can tune out the rear O2 sensor, but it requires the tuning software and a laptop to tune it. If it were me, I'd replace the cat and both sensors as their avg. life seems to be around 90-110K miles anyways. The cat is a bolt on piece and you can replace it yourself on a good set of ramps in about an hr. if things aren't frozen up too badly.

[3100 MPFI]

There is a way to get rid of the rear O2 sensor, but if you have emissions in your area, I would NOT recommend it.

You can buy an O2 SIMULATOR (or emulator as they are sometimes called). It should just plug into your stock connector and it will FOOL your computer into thinking you have a working rear O2. After this is installed, you can remove the cat.

I am going to use the O2 simulator in my 1988 Cutlass Supreme when I finish the OBD2 conversion so that it will run without throwing a code, and I don't have to get the rear O2 welded in.

[IsaacHayes]

You can loosen the bolts on the downpipe and drive it shortly to see if power is up. Don't drive it long like this because the gases can burn stuff. They are spring loaded bolts. Do you hear any clicking if you get on it? That is usualy when the cat is so clogged that the downpipe gets pushed open and the spring loaded bolts snap back closed.

[PCGUY112887]

Just curious, say you have emissions in your state and all they do for 96+ cars is an OBD scan to ensure your cat is OK. No visual and no sniffer. If you tune the rear O2 sensor out, will their "checking program" error since it won't be able to find it at all?

Reason I ask is because that is how it is in IL, I planned on just tuning it out with my DHP but I am afraid their program will have a shit fit if I do. I know if I use the simulator I will be good, but hate to buy something else.

[98malibu3.1]

Eliminating the factory cat is worth only 2-3hp at most. Unless you are running a very mean all motor or forced induction motor, then I would just replace the cat and be done with it. Find them on ebay for like $80 or so I'm sure.