ECU Hot Engine During Deceleration

PURPOSE: Check that during deceleration the OCR has a fixed value of 50%.
Preliminary conditions:
Coolant temperature above 40°C.
Tachymetric relay and ECU connectors in place.
Start the engine.
Stabilize engine speed at 1900 RPM.
OCR value must change with the regulation.

Fig. 7 Throttle Plate Housing:

Close the microswitch (3), Fig. 7.
OCR value should = 50 % (45° on dwell meter).
1. If OCR value is incorrect:
a. Stop the engine (key switch OFF)
b. Remove the ECU connector

Fig. 30 Underhood view:

c. Remove the twin-speed relay (M772), Fig. 30.

Fig. 23 ECU connector pins # 6, 12:

d. Connect an ohmmeter between terminal 6 and ground, Fig. 23.
2. Idle position (microswitch closed). Resistance should be below 1 ohm.
3. Accelerated position (microswitch open). Resistance should read "infinity". If not, check the microswitch and the electrical circuits continuity.
NOTE: The OCR value blocked at 50% shows up only a few seconds on the duty cycle meter of dwell meter.
4. Reconnect the ECU connector.