Toyota Corolla 1970-1987 Repair Guide

Cold Start Injector

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See Figures 1 and 2

During cold engine starting, the cold start injector is used to supply additional fuel to the intake manifold in order to aid in initial start-up. The opening and closing of the injector is determined by the start injector time switch, located in the thermostat housing. When the engine coolant temperature falls below a certain point, the switch is tripped which opens the cold start injector. As the engine coolant warms up, the switch will eventually close the injector.



Click image to see an enlarged view

Fig. Fig. 1: Cross-sectional view of cold start injector

REMOVAL & INSTALLATION




CAUTION
Perform this operation on a cold engine only!

  1. Disconnect the negative battery cable. Relieve the fuel pressure.
  2.  
  3. Remove the cold start injector union bolt on the delivery pipe.
  4.  

Before removing the union bolt, place a suitable container under it to catch any escaping fuel



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Fig. Fig. 2: Cold start injector mounting

  1. Disengage the wiring connector at the injector.
  2.  
  3. Unscrew the two mounting bolts and then remove the cold start injector from the air intake chamber.
  4.  

To install:
  1. Installation is in the reverse order of removal.
  2.  

Always use new gaskets when reinstalling the injector

  1. Start the engine and check for any leaks.
  2.  

TESTING



See Figure 3

  1. Unplug the wiring connector and remove the cold start injector from the air intake chamber.
  2.  

Do not disconnect the fuel line

  1. Remove the rubber cap from the fuel pump check terminal and short both terminals with a jumper wire.
  2.  
  3. Using Special Tool 09843-30011, connect one end to the injector and the other to the battery.
  4.  
  5. Hold the injector over a suitable container and then turn the ignition switch to the ON position. Do not start the engine.
  6.  
  7. Check that the fuel splash pattern is even and V-shaped.
  8.  
  9. Disconnect the test probes from the battery and check that the fuel does not leak from the injector tip any more than one drop per minute.
  10.  



Click image to see an enlarged view

Fig. Fig. 3: Cold start injector testing-the fuel spray pattern should be even and V-shaped

  1. Remove the Special Tool and install the cold start injector.
  2.  
  3. Check the resistance of the injector. It should be 3-5 ohms.
  4.  
  5. If the cold start injector did not operate properly in any of these tests, it will require replacement.
  6.  

 
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