Health check
Start the engine at idle.
Check each valve individually with a stethoscope with the engine running to see if it makes a click. A click accompanies each opening and closing of the valve nozzle.
If there is no stethoscope, then the valve can be checked with a screwdriver or finger.
If an unnatural noise or no noise is detected, the plug connection, control unit signal or injection valve resistance must be checked.
Resistance test
Switch off the ignition.
Check the resistance of all injection valves with an ohmmeter (pic. G-2210). Its value for motors of all types should be 13.8 ohms.
If the measured resistance value does not match the specified value, the injection valve must be replaced.
To check the injection jet and the tightness of the valve, special tools are required, which are available only in specialized TOYOTA workshops.