Toyota Pick-ups/Land Cruiser/4Runner 1970-1988

Automatic Choke System



Carbureted Models Only

The purpose of the automatic choke is to temporarily richen the air/fuel mixture to the engine by closing the choke valve when the engine is cold. By shutting the choke valve you are effectively choking the engine by reducing the amount of air which is allowed to enter the carburetor. This then enables the air/fuel mixture to be ignited sooner (faster).


See Figure 1

Checking the Automatic Choke System
  1. Check the choke housing its hoses for any leaks, cracks or other damage.
  3. Check that the middle mark on the thermostatic case is aligned with the mark on the coil housing.

Loosen only the three screws around the outside edge of the case. Do not loosen the bolt at the center of the case because it will allow coolant to come out.

  1. Remove the top of the air cleaner.

Click image to see an enlarged view

Fig. Fig. 1: A close-up view of the choke housing

  1. With the engine cold and turned off, press down on the gas pedal and release it. The small valve in the center of the carburetor bore should be almost completely closed.
  3. Run the engine until it reaches normal operating temperature and then check that the choke valve has opened up.
  5. Reinstall the top of the air cleaner.