Fuel Injectors, Testing

Fuel Injectors, Testing







Special tools and equipment
- VAG 1526 A
- VAG1527 B
- VAG 1594 A
- VAG 1598/31

Testing internal resistance







- Remove engine cover panel -1- -arrows-.
- Unplug connector from injector to be tested.







- Connect multimeter to valve (resistance measurement range)
- Specification: 12 to 13 Ohms (at room temperature)

If the specification is not attained:
- Replace the injector.

If the specification is obtained:
- Check voltage supply.

Checking voltage supply

Requirements for test:
- Fuse for injectors OK.
- Fuel pump relay OK. Testing. Testing and Inspection

- Unplug connector from injector to be tested.







- Connect VAG 1527 B voltage tester as follows:

Connector Contact Measure against
1 Engine Ground

- Switch on ignition.
- The LED should light up.

If the LED does not light up:
- Test for open circuit in wiring between contact 1 and fuse for injectors
- Correct any open circuits.

If the LED lights up:
- Test activation of injectors.


Testing activation

Test requirement:
- Internal resistance of injector OK.

- Slide back rubber sleeve on connector for injector but do not unplug the connector.







- Connect VAG 1527 B voltage tester between contact 2 (signal) and contact 1 (positive).
- Operate the starter briefly. (The engine can be allowed to start.)
- The LED should flash.

NOTE: The LEDs on voltage testers with a low current draw continue to glow faintly between impulses from the engine control module(rather than going out completely) and become much brighter when receiving an impulse.

If the LED does not flash:
- Connect test box VAG 1598/31 to wiring harness for engine control module. Do not connect to the engine control module itself. Scan Tool Testing and Procedures







- Test for open circuit and short to positive or Ground in the following wiring connections:







- Correct short circuit or open circuit if necessary.

If the wiring is OK:
- Install a new engine control module.