Fuel Injectors & Fuel Distributor Tests

Fig. 3 Installing test relay 5170:

Fig. 8 Fuel injector volume test:

1. Remove injectors from cylinder head, then snap retaining clips off and pull injectors out. Do not disconnect fuel lines.
2. Connect tool 5014. This fixture contains a set of calibrated measuring tubes to record the flow of each injector, Fig. 8. An extension hose must be slipped over the end of each injector in order to make the hook-up.
3. Install fuel pressure gauge as outlined under ``System Pressure Tests.''
4. On B-21 engines, remove the bellows from the air sensor so the sensor plate can be reached. On B-28 engines, remove the air cleaner.
5. Switch on the ignition.
6. Install test relay 5170 to activate fuel pump, Fig. 3.
7. Set gauge lever in position 1 (toward fuel distributor).
8. Lift (on B-21) or depress (on B-28) the air sensor plate fully and hold it there for approximately 4 seconds. Line pressure may drop no more than 4.2 psi (.3 kp/cm2). If pressure drops excessively, the following reasons are indicated:
a. Low fuel level in tank.
b. Clogged fuel lines or filters.
c. Fuel line leakage or insufficient fuel pump capacity.
9. To check fuel pump capacity, disconnect the fuel delivery line at the fuel distributor; run the pump for 30 seconds into a calibrated measuring container. Minimum quantity is 25 oz. (750cc).