Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
1994 Audi CabrioletFACTORY OEM SERVICE PROCEDURE
Oxygen Sensor (O2S) Control
- Disconnect O2S connector. Refer to the ELECTRICAL COMPONENT LOCATIONS table at beginning of article. Measure resistance between engine ground and O2S connector terminal (component side of connector). If resistance is not infinite, replace O2S.
- If resistance is infinite, set voltmeter on 2 volt DC scale. Turn ignition on. Measure voltage between engine ground and O2S connector terminal (component side of connector). If 350-450 millivolts are present, O2S is okay. If 350-450 millivolts are not present, check wiring. If wiring is okay, replace ECM.
NOTE:
Throttle position sensor is automatically adjusted when throttle position switch is adjusted.
Factory Service Tools
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
Disclosure: Verified tool recommendations may earn an affiliate commission at no cost to you.
When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.