I have a 1994 Z28 and I am having my exhaust done soon and plan on taking out the cat. I was told if i take out the cat that my SES (service engine soon) light will appear. I also heard that it might not appear on the older models 93, 94, 95, and 96. I know they make a O2 sensor (OBD II) for the new models, but do they make one the year i have and is it nessasary for me to get one? If anyone has a catless exhaust and can help me, i would be very thankful.

 

Your car has O2 sensors before the cats and none after, so removing the cats won't throw a code. OBD2 cars will throw a code if you remove the cats and leave the O2's connected. OBD2 cars have sensors pre and post cat.

 

and change your O2 sensors. you won't be sorry.

got mine for $28 ea Combination Motorsports in Las Vegas

 

So MrBig, you don't have any problems with your car, why would i need new o2 sensors? Also will this affect my gas mileage or performance?

 

Replacing O2's should be part of regular maintenance and depending on their current state new ones could definitely help with performance or fuel economy. I change mine every two or three years now that I am supercharged just added insurance. I have heard lots of horror stories about O2’s of different manufactures. IMO you should stick with ACDelco’s.

Kris

 

Ditto, good advice. O2s rarely go bad all at once. They tend to go bad over time and loose their accuracy along the way. Cheap and easy PM to change them on a regular basis and ensure top performance. Yes, stick with AC-Delcos.

 

yes, your mpg will pick up if they are old. mine were original i think! (70K miles) so i did feel a diff and am doing a 1,000 mile mpg test as we speak.