Originally Posted by Saturn Simon
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?
Depends. Most generic aftermarket O2 sensors just don't like the 3800. GM has a parts website, www.gmpartsdirect.com
for your 02 sensor. I believe in leaving GM o2 sensors in the 3800, thats when they get maximum performance, and the very best gas mileage.
But yes, the computer also has to relearn the information, so disconnect the battery, key on, leave it for 10 minutes, drain the ECM of any stored memory. Plug the battery in, and take it for a drive, it shoud work well after a while.