This is actually for my friends 87 Supra Turbo, but I might need the information later. He is planning on taking his cat off and running the exaust from his exaust manifold collector to the muffler. What does he need to do to his O2 sensor to keep the check engine light from coming on? I think you guys have mentioned this when talking about test pipe installation. Thanks in advance.

 

Measure the resistance or voltage on the O2 sensor under normal operating conditions, then match that resistance/volatge when disconnected with a resistor or 2, just tricks the computer.

 

Put a piece of black tape over the bulb or cut the wire

 

your friend with the supra wont have any problems.

 

ISn't a 87 supra OBI? In that case, he wouldn't have any check engine light probs.