In 2007, Camry 240G, occasionally idling too low, turned off the engine, washed the throttle, and appeared again after driving for a while. What should I do?

The reasons are: the idle air metering hole is blocked, the idle device is not working normally, the spark plugs of individual cylinders are too weak, the seals of individual valves are not tight, the intake manifold leaks air, the ignition time is too early or too late, and the idle speed is not adjusted properly. When the idle speed of the engine is unstable, the idle speed should be adjusted first. If the fault cannot be eliminated after idle speed adjustment, check whether the idle metering hole and idle air metering hole are blocked. If the metering hole is blocked, clean it with gasoline or acetone and blow it with compressed air. If the metering hole is not blocked, to stabilize the engine speed at a certain speed, you can observe whether the middle and lower gaskets of the intake manifold or carburetor are leaking. If there is air leakage, it can be eliminated by fastening screws or adding or subtracting gaskets. If the idle speed is unstable and the engine power decreases, the working condition of the spark plug, the sealing performance of the valve and the ignition time should be further checked, and maintenance and adjustment should be carried out if necessary.

When the engine turns off at idle speed, the idle speed should be adjusted according to the actual situation. After adjustment, if the fault disappears, it is improper adjustment of the idle screw. After adjustment, if the fault can't disappear, you can turn on the throttle and let the engine continue to run. Check the carburetor and intake manifold gasket for air leakage with cotton yarn or paper. If there is no air leakage, you can remove the idle metering hole for inspection, blow through the idle oil circuit at the same time, and then reassemble the test. If the fault disappears, the idle metering hole and idle oil circuit are blocked. For carburetor with idle stop valve, check whether the electromagnetic coil circuit of idle stop valve is normal. If the idle fuel-saving metering hole is blocked due to abnormal electromagnetic coil circuit, repair the idle stop valve.