Join Date: Mar 2002
Location: Austin, TX, USA
If you plan on hanging onto that 89 and working on it yourself you should get a scan tool for it. Occationally you can find them in pawn shops or ebay. I would expect you can get one for less than $100. You would probably see a cost savings on swapped parts for the investment.
The way to check an O2 sensor is to look at the cross counts. There are also O2 testers, but for the same money you can have a full diagnostic tool that will do much more.
68 Coupe, 350 w/ Edelbrock Performer RPM heads, cam, intake, 700R4, Dave's small body HEI