Deceleration Fuel Cut-Off System: Testing
- Check throttle switch by disconnecting wiring connector from switch. Use an ohmmeter to make sure there is a good connection between throttle switch and ground when the throttle switch is released. Reconnect wiring to switch.
- Connect Bosch test meter (KDJE 7453) to 2-pole test socket located near relay holder. With engine at operating temperature run at idle speed. Disconnect electrical connection from vacuum valve.
- Using voltmeter, check that there are 12 volts between connector and ground. Reconnect wiring to vacuum valve and increase engine speed to 2000 RPM. Suddenly release accelerator.
- Using hand, feel if vacuum valve is operating. Check that Lambda system assumes a fixed pulse relation (60%) until system cuts out at 1375 RPM.