Fuel Injector: Testing and Inspection

***UPDATED BY TSB 8420, MAY 1984
***UPDATED BY TSB 8446, SEPT. 1984

1. Check injector harness for proper connection.
2. Run engine and listen to injector with mechanic's stethoscope. Should have solid clicking sound. Compare to other injectors.
3. Pull electrical connector from injector while listening with stethoscope. Sound of click should change.
4. Connect pulse duration tester and note duration in milliseconds. At idle, should be:

Engine Cold 60 °F, Cranking 6.4 ms
Cold engine starts 4.5 ms
Warm-up after one minute (approximately) 3.8 ms
Engine at normal temperature, idling no load 2.5 - 2.7 ms*

*Depending on CO at Idle

5. Stop engine.
6. Remove electrical connector.
7. Measure resistance through injector connector pins. Should be approximately:

.8 ohms

8. If injector spray pattern or injector contamination is suspect, refer to TSB's for testing procedures.