Fuel Injection

TESTING PROCEDURE:

NOTE: While trouble shooting, always check the wiring, fuses and connectors for good condition and routing. Also check ground locations for good connection. Use the wiring diagrams found in SCHEMATIC DIAGRAMS to supplement your testing efforts.

Color Code Legend:

Checking ECU Ground Connections:

1. Turn ignition OFF.
2. Access fuel injection ECU by removing the passenger side kick panel and glove compartment.
3. Check fuel injection ECU ground connections. They should make good contact and fit tight.

Removing ECU Connector:

4. Remove the ECU connector by pressing up the latch and folding out the wire cluster.

Removing Protective Cover:

5. Remove connector protective sleeve.
CAUTION: ^ Never check connections from the front. Connectors can get damaged and worsen the problem.
^ Check connections through the holes in the connector.
^ Connection pin numbers are printed on the connector side.

Removing Rubber Boot:

6. Check the air mass meter by removing the rubber sleeve from the connector to access wiring.

Checking Terminal #5:

7. Connect a lead between ECU connector pin 21 and ground.
8. Connect the voltmeter between ground and terminal #5 (positive lead from system relay) at air mass meter.

Reading: approx. 12 volts

a. If reading is incorrect, check and repair wiring from the air mass meter to the system relay.
b. If reading is correct, continue with next steps.
9. Connect the voltmeter between terminals# 1 (ground) and 5 (positive lead from system relay).

Reading: approx. 12 volts

a. If reading is incorrect, check and repair wiring from the air mass meter to ground and retest.
b. If reading is correct, continue with next steps.
10. Remove the lead between pin 21 at ECU connector and ground.

Checking Pins 6, 7 And 14:

11. Connect an ohmmeter between pin 6 and 7 at ECU connector.

Reading: approx. 3.7 ohms

a. If reading is incorrect, check and repair wiring from the ECU connector to the air mass meter. If no fault can be found, replace and retest with new air mass meter.
b. If reading is correct, continue with next steps.
12. Connect an ohmmeter between pin 6 and 14 at ECU connector.

Reading: 0 - 1000 ohms depending on CO-adjustment screw position

a. If reading is incorrect, check and repair wiring from the ECU connector to the air mass meter. If no fault can be found, replace and retest with new air mass meter.
b. If reading is correct, proceed with next step.

Assemble Connector:

13. Keep air mass meter rubber sleeve removed. Disconnect the test equipment. Reconnect the ECU and all other connectors, install the kick panel and glove compartment.
14. Start engine and run to operating temperature (coolant temperature must exceed 140°F (60°C).

Checking Terminals #1 And #4:

15. Connect a voltmeter between terminals #1 and #4 of air mass meter.
16. Increase engine RPM to over 2100. Than turn off engine.
17. After 4 seconds the voltmeter pointer should swing for about 1 second to show hot-wire burn-off cycle.
a. If voltmeter does not indicate burn-off cycle, replace and retest with new air mass meter.
b. If reading is correct, air mass meter is in good condition.
18. Disconnect test equipment and reconnect rubber boot over air mass meter connector.