my SES light came on last night-about 300 miles after borla cat back install- and i got it scanned at autozone and it came up catalyst inefficiency. The borla was welded on by a shop (b/c i bought it used and it was welded already)- could the heat from welding blow the O2 sensors? I HIGHLY doubt that my cats are bad b/c I haven't touched them and I only have 23k miles on the car. I'm leaning toward putting O2 sims on the car to fix this problem. I don't have to pass emissions here so even if the cat is blown, it's not a huge deal to me. Is there any problem with throwing on O2 sims to "fix" this?

 

oh-this is on my 01 WS6 btw.

 

clear the computere and see if it comes back.

 

how do i clear the computer?

 

Check the exhaust very closely too. An exhaust leak can sometimes give a false reading to the O2 sensor and throw that code.

 

you mean a leak before the sensor correct? Could a leak AFTER the sensors cause the false reading?

Will O2 sims make this go away b/c I'd rather do that than replace sensors?

 

It could if it is pretty close to the sensor. It's a lot cheaper to reweld it and fix the leak than buy O2 sims. It could also be that the catalyst in the converter is bad as well, so O2 sims will keep the SES light off. Although they will be masking the problem rather than fixing it. If the converter melts or plugs up you will have even bigger problems.
I would probably check for exhaust leaks and reset the ECM.

 

i was told that there is an 8 year 80k mile warranty on emissions parts so i was gonna take it to the dealer this week. Another person said he had the same thing happen at 24k miles on an 01, same mods. weird.

 

This is the second time I've seen reference to an 8 year 80,000 mile warranty on cats. I would be grateful to anyone that can point me to some documentation on this that I can take back to the dealer who charged me a small fortune to replace my O2 sensor and converter at 58,000 miles only to have the SES light come back on a month later!

 

the deal knew all about it-they said it was on all emissions equipment. You have to watch out for some dealers-I've run into some pretty shady ones. This last one was the best I've ever dealt with though.