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.
1999 Audi A4 Base, 1.8 B, AutomaticFACTORY OEM SERVICE PROCEDURE
Connector Identification
CONNECTOR IDENTIFICATION DIRECTORY
| Connector | See Fig. | |
|---|---|---|
| Camshaft Position Sensor Connector Terminals | 3 | |
| ECT Sensor Connector Terminals | 4 | |
| ECT Sensor Terminals | 5 | |
| EGR Temperature Sensor Connector Terminals | 6 | |
| EGR Vacuum Regulator Solenoid Valve Connector (Harness-Side) Terminals | 6 | |
| Engine Speed Sensor Connector (Harness-Side) Terminals | 3 | |
| Engine Speed Sensor Connector (Sensor-Side) Terminals | 7 | |
| EVAP Canister Purge Valve Harness Connector Terminals | 6 | |
| EVAP Differential Pressure Sensor Connector (Harness-Side) Terminals | 3 | |
| EVAP Leak Detection Pump (Component-Side) | 8 | |
| EVAP Leak Detection Pump (Harness-Side) | 9 | |
| Fuel Injector Harness Connector | 6 | |
| HO2S Black 2-Pin Heater Connector | 6 | |
| HO2S Connector (Harness-Side) Terminals | 10 | |
| HO2S Connector (Sensor-Side) Terminals | 11 | |
| IAC Valve Connector Terminals | 12 | |
| Ignition Coil Power Output Stage 3-Pin Connector (Harness-Side) Terminals | 3 | |
| Ignition Coil Power Output Stage 4-Pin Connector (Harness-Side) Terminals | 13 | |
| Intake Manifold Change-Over Valve Connector Terminals | 6 | |
| Knock Sensor Connector (Harness-Side) Terminals | 3 | |
| Knock Sensor Connector (Sensor-Side) Terminals | 7 | |
| MAF Sensor Connector Terminals | ||
| A4 (1.8L Turbo) | 14 | |
| A4 (2.8L) | 3 | |
| Secondary Air Injection Solenoid Valve Harness Connector | 6 | |
| TP Sensor Connector Terminals | 15 | |
| TP Sensor Terminals | 16 | |
| Throttle Valve Control Module (TVCM) Connector Terminals | 17 | |
Factory Service Tools
Use the Manual With the Right Hardware
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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.