Engine light came on and said O2 sensors bad so changed all four,light still coming on back on but only when i come on to it.I have SLP exhaust,not sure what the problem is and we are all stumped!!

 

Did it say if it was the primary or secondary (post-cat) oxy sensors? If the error is showing a post-cat sensor, then the problem could be with a bad cat converter.
Btw, this post is in the wrong section, you want the 4th gen section.

 

need to scann it for codes and let us know what they are. if there are any mods around this needs to be moved. oh and what yr and model?

 

thanks for movin it arrow.

 

98 camaro z28 ls1 i will check the code #'S

 

what do y mean bye any mods around this have to be removed.

 

there are 4 of them that i changed on the exhaust itself.

 

Its the sensors on the exhaust itself not on the cats,thinking it may be a bad ground?

 

moved not removed

 

You have two oxy sensors before the cats, and two after the cats. The two after monitor the cats to make sure they're performing as they're supposed to. If not, it will trip a code and the check engine light will go on. Those two sensors don't alter engine runnability like the pre-cat ones will. That's why you need to see which error code you get, it will specify which sensor(s) it is.