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 S4FACTORY OEM SERVICE PROCEDURE
Diagnostic Tests: Notes
NOTE:
To properly diagnose vehicle, it is recommended to use connector test kit (VW 1594) and scan tool (VAG 1551) with harness adaptor (VAG 1551/1). See Figure
. All voltage and continuity tests should be performed with a Digital Volt-Ohmmeter (DVOM) with a minimum 10-megohm input impedance. After any repairs are made, erase DTC memory and test drive vehicle. See CLEARING CODES
and TEST DRIVE
. Recheck DTC memory and verify DTC does not set again. If DTC sets again, perform testing procedure again.
Factory Service Tools
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
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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.