Today I changed the oxygen sensor in my 1988 SSE for a brand new one. I followed the instructions in the Haynes manual to the letter, I was careful removing the old one and putting the new one in.... But when I started the car afterwards in ran worse than ever!!!

What did I do wrong?!

Did you unhook the battery while you did the work?

No. Would that make any difference?

Yes. It could make all the difference. The PCM had "learned" the old sensor. it needs to "learn" the new one. Unhook it for 10 minutes, negative cable first.

So if I disconnect the battery now for 10 minutes it should be fine?

Thanks!

I think so.

Yah I would say the same thing...battery definitely...it knows when its goin bad, but it never seems to know when its new....wierd cars...

also, was it pregreased? if not make sure to put some high temp grease or lead grease on there because it will not be too fun getting it back out the next time if its not greased. Just a tip

Yeah, it was pre-greased fortunately.

Thanks guys!

What brand of O2 did you buy?

I forget what it was now. :? I ordered via USAutomotive a US car parts specialist based in the UK so I basically just had to take what they sent me.

Do they vary much in quality then?