Injectors, Checking

Injectors, Checking

NOTE: To gain access to the injector connectors, the engine cover and air cleaner housing must be removed.

Electrical check on injectors
- Disconnect connector at injector to be checked.







- Connect portable multimeter to injector for resistance measurement.
Specification: 13...16 Ohm

NOTE: With warm engine, injector resistance increases by approx. 4...6 Ohm.

If reading does not match specification:
- Replace injector.

If reading matches specification:
- Check power supply.

Checking power supply
- Disconnect connector at injector to be checked.







- Connect diode test lamp for voltage measurement to socket 1 of connector and Ground.
- Operate starter for several seconds (engine may start).
Specification: Diode test lamp must light

If diode test lamp lights:
- Check wiring.

If diode test lamp does not light:







- Check for continuity in wiring from socket 1 via fuse for injectors to fuel pump relay and eliminate open circuit if necessary.

Checking wiring
- Switch off ignition.
- Disconnect connector at injector to be checked.
- Connect test box V.A.G 1598/31 at wiring harness to engine control module. Actual engine control module is not to be connected. Wiring And Component Check Using Test Box V.A.G 1598/31







- Check for open circuit and short to Ground/positive in following wiring:







- Eliminate open circuit in wiring/short circuit if necessary.
- If wiring is OK, replace engine control module.