65438+2.5, 2002 Camry's idle speed is unstable or high after cleaning the throttle, and it can't be reconnected after power failure for more than ten minutes, so the computer can't detect it. Why?

Engine jitter has the following reasons:

1, the engine has serious carbon deposits, and the most common car with serious jitter is that the fuel injector throttle is too dirty or has too much carbon deposits;

2, ignition system problems, check the working conditions of spark plugs, high-voltage lines and ignition coils;

3. The oil pressure is unstable. If the supply pressure of the pump is abnormal or the intake pressure sensor is wrong or not working well, the body will shake;

4, engine parts aging; Excessive carbon deposition in engine exhaust will adsorb carbon in gasoline of cold-start injector, which will lead to too thin cold-start mixture and difficult starting.

The serious idle vibration is generally caused by engine cylinder missing, rubber aging or loosening, carbon deposition, fuel system failure and other reasons.

1. Serious engine carbon deposit: There have been carbon deposit problems in automobiles, including cylinder carbon deposit, throttle carbon deposit, spark plug carbon deposit, intake carbon deposit and so on. When the engine has too much carbon deposit, it will affect the ignition energy, intake efficiency and air-fuel ratio of the automobile, resulting in unstable power output, idle speed and acceleration jitter.

2. Unstable oil pressure: If you have cleaned the engine carbon deposit, cleaned the throttle, replaced the oil pad and spark plug, etc. And the body is still shaking when idling. I suggest you go to the 4S shop to check whether the oil supply pressure and intake pressure sensors are normal. If the oil supply pressure of the oil pump is abnormal, or the intake pressure sensor is wrong and works badly, it will lead to the body shaking.

3. Engine cylinder shortage: Engine cylinder shortage mainly refers to the abnormal operation of one or more cylinders of the engine, which is generally manifested as: the exhaust gas flowing out of the car is obviously intermittent, the exhaust pipe is violently shaken, and the engine jitter can be obviously felt, sometimes accompanied by abnormal noise. This is mostly related to ignition coil failure.

4. Aging of engine parts: Car jitter is also related to the aging of engine feet (also known as claw pads). The engine foot is actually the damping system of the engine. The engine feet are responsible for absorbing slight vibration when the engine is running. If there is something wrong with the engine base, these vibrations will be transmitted to the steering wheel and cab, causing idle vibration.

Solutions;

The best way is to clean the oil circuit and clean it regularly. There is no specific experience in engine development parameters from new cars. In addition, with the continuous improvement of emission standards, it can not adapt to the changes of fuel. It is impossible for all engine manufacturers to solve this jitter problem in a short time. In addition, the fuel quality is not very good or the fuel storage time is too long at the beginning of the new car, which leads to the rapid increase of colloidal components in the oil circuit, which will continuously pollute the fresh fuel, resulting in no good fuel to participate in the combustion in the later stage, resulting in excessive carbon deposition. Only by maintaining a clean oil circuit can most problems be gradually alleviated. Using fuel additives such as PNF stock solution can solve the above problems caused by carbon deposition.