Warm DRIVEABILITY Test 3 - Choke Position With Engine Running Check

1. Remove air cleaner lid. Start engine. Observe choke plate position. Choke plate should be fully open. If choke position is okay, proceed to WARM DRIVEABILITY TEST 4  (4-Bbl. models) and WARM DRIVEABILITY TEST 5  (2-Bbl. models). If choke position is not okay, connect a voltmeter to the choke heater wire at the choke control switch terminal and ground. Voltage reading should be within 1-volt of battery voltage.
   Fig 1: Choke Control Switch Terminal

   
2. If voltage reading is within specifications, turn ignition off (2-Bbl. models). Disconnect wire from choke control that goes to the electric choke heater. Connect an ohmmeter between the choke heater wire and the choke heating element retaining screw. Ohmmeter reading should be 4-12 ohms. If resistance is not within specification, replace choke heating element. If resistance is okay, check and repair choke linkage for sticking or binding.
   Fig 2: Electric Choke Heater

   
3. On 4-Bbl. models, connect voltmeter to choke heating element harness connector and ground. Voltage reading should be within one volt of battery voltage. If voltage is okay, check choke linkage for binding. If choke linkage is okay, replace the choke heating element. If voltage is not okay, repair open circuit in wiring to the choke control switch.
   Fig 3: Choke Heating Element Harness Connector & Ground

   
4. If voltage reading in step 2) is not within specifications, connect voltmeter to ignition feed wire connector of the choke control switch and ground. Voltage reading should be within one volt of battery voltage.
   Fig 4: Ignition Feed Wire Connector

   
5. If voltage is within specifications, replace choke control unit. If voltage is not within specifications, turn ignition off. Disconnect oil pressure switch connector. Connect voltmeter to engine harness connector at oil pressure switch terminal "C" and ground.
   Fig 5: Oil Pressure Switch Terminal

   
6. Turn ignition switch to the "RUN" position. Voltage should be within one volt of battery voltage. If voltage is not within specification, repair harness to ignition switch for an open circuit. If voltage is within specification, disconnect ignition feed wire from choke control switch.
7. Connect an ohmmeter between the engine harness connector at the oil pressure switch terminal "A" and choke control switch wire. Ohmmeter should show continuity. If there is continuity, replace oil pressure switch. If there is no continuity, repair harness for an open circuit.

Fig 6: Choke Control Switch Wire