Ok have been reading the boards and am now more than a lil confussed.
I have a series 1 N/A engine.
What should I replace in a tune up, and what is the recommended brands etc.

Gas milage is dropping severly so figure its prob time for a good tickle up under the hood.

Thanks
AJ

Possible an O2 sensor? AC Delco only. Definatly not Bosch.
PCV valve, brand doesn't matter IMO (cheap an uncomplicated)

The general tune up would be

Plugs
Wires
PCV
Checking TB if it needs cleaning
Look over MAF for cleaning
Review gas mileage for O2 replacement

Full tune up
Plugs
Wires
PCV
Remove TB for cleaning (requires gasket)
Remove MAF and clean seperately from TB
Change O2 sensor
Possibly a coolant flush and fill

AC Delco list 2 possible sensorsfor the 1993 SSE. AFS20 or AFS21
How do I know which one I need? or does my car have 2? one before the converter and one after.

Thanks
AJ

Just one before the cat. I think it'* AFS-20. Should just have one wire.

L27'* got the HO2 sensor. Check your emissions label. If it says "HO2" on it instead of "O2", you DON'T have the single wire.

In other words, if you're heated on the O2 filament, you don't use the same sensor as the L67 engine.

Here'* what you're looking for on the radiator core support:


This is from a 93 L27. My bet is yours is HO2S.




This is from a 93 L67. Tell us which you have, we'll tell you the right sensor part number.

Throttle Body and MAF sensor cleaning is in Techinfo, the link at the top of the page.

Sorry, I didn't think any got the heated sensor till 94.

ok after a quick trip next door to the car wash so I had light, mine lists HO2..... So am I right in thinking this takes a heatd one?


Thanks
AJ

Yep.