Contents Section: Testing & Diagnostics All sections

Early Fuel Evaporation System Isuzu Trooper I

Testing & Diagnostics 1 illustration ~145 words

DESCRIPTION

The Early Fuel Evaporation system uses a ceramic heater grid located underneath the primary bore of the carburetor. The grid heats incoming air/fuel mixture for improved vaporization and driveability during cold engine operation.

Scheme 1: Early Fuel Evaporation System EFE heater located in carburetor insulator gasket.

OPERATION

When ignition switch is in the "ON" position, voltage is applied to a thermo switch located in intake manifold. If engine coolant temperature is below a calibrated value, the thermo switch completes the circuit to the heater, and allows current to flow.

The heater, incorporating a positive temperature coefficient semiconductor element, increases in temperature and then self- regulates at a calibrated temperature. This is in effect except at high engine speeds when air/fuel flow will reduce the temperature below regulated value. When coolant temperature reaches calibrated value, thermo switch turns off and current to heater is cut off.

SYSTEM TESTING

Note. Testing information is not available.