Fuel Injectors & Circuit: 2.0L

Ensure engine speed sensor and its circuit are okay. Check injector triggering using OUTPUT DIAGNOSTIC TEST MODE. See appropriate TESTS W/CODES - GASOLINE article.
If necessary, disconnect Engine Coolant Temperature (ECT) sensor. Adjust Digital Potentiometer side "A" of scan tool to 15 ohms. See Fig 1 . Connect potentiometer to ECT sensor using test leads from Adapter Kit (VW 1594).
Remove upper part of intake manifold. Remove fuel rail, leaving fuel lines and injectors attached. Place injectors in Fuel Analyzer (VAG 1602). Disconnect ignition coil.
Crank engine and observe injectors. Injectors must spray uniformly while pulsating. Turn ignition off and check fuel injectors for leaks. No more than 2 drops per minute are permissible. When reinstalling fuel rail, ensure "O" rings are not damaged.

Fig 1: Testing Fuel Injectors & Circuit (2.0L)

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