What happens if you disconnect your oxygen sensor?

Disconnecting your oxygen sensor can lead to several issues, including decreased engine performance and fuel efficiency. The vehicle's engine control unit (ECU) may not receive accurate readings, causing it to run rich or lean, which can result in increased emissions and potential damage to the catalytic converter. Additionally, the check engine light may activate, leading to diagnostic trouble codes that could complicate future repairs. Overall, it's advisable to keep the oxygen sensor connected for optimal vehicle operation.