market dynamics
Where is the reason for the high or unstable idle speed of electric jet motorcycle?
Release date:2021.04.01

Electric spray motorcycle if there is idle instability, high or low, or even flaming out is a very headache, because the electric spray car is not like carburetor models, adjust the idle screw can be solved.

For common electric spray truck, such as the use of Delphi electric spray system, if the above situation, and accompanied by the fault light, it means that the idle control system has a problem, at this time if the fault detector to read the fault code, usually show P0505 fault code.

The meaning of the P0505 fault code is that the difference between the actual idle speed and the target speed exceeds the specified value within a limited time. In general, this is a fault code that tells the repairman that the ECU can no longer keep the engine running at the expected speed.


To report this fault code, two conditions need to be met:

One is that the speed difference exceeds the calibration value. For example, it was calibrated to be within 150 RPM, but the actual difference was greater than 150 RPM.

The second is to meet the maintenance time. A difference of 150 RPM is not an immediate code signal, but a period of time should be maintained, for example, the speed out of tolerance lasts more than 20 seconds.

If the above two conditions are met, P0505 is stored and displayed by the fault light, and can also be read by the detector.

For the initial stage of electric injection maintenance, when we see the fault code, especially after we understand the meaning of the fault code, we often find the idle valve directly and replace the idle valve. This is actually the inertia of the idea of replacement maintenance in the era of carburetor.

For efi motorcycle maintenance, this method is not desirable, because this fault code is the ECU control speed and compare the final logic judgment and quote us the fault code, not like some of the sensor is through direct judgment signal voltage range, so involved with wider range of components, and therefore can not repair it narrowed down to the idle speed control valve, need step by step, from big to small narrow range find point of failure.

At the time of inspection, first of all, it is necessary to ensure that the basic functions of oil, electricity, gas and machinery should be normal, and the engine temperature is appropriate. If it is a water-cooled car, the water temperature should be above 70 degrees, so as to ensure that the engine has a normal working environment, and there will not be some indescribable interference that affects the judgment.

At the same time, the throttle voltage is also a must check item, the throttle is at the fully closed idle position (the throttle voltage value of the fully closed throttle meets the ECU identification requirements, and then the idle closed-loop control can be carried out). In general, the sensors are generally fine for further confirmation.

In general, preliminary anomaly checking can be performed by reading the data stream.

Delphi has a BLM cell in the data stream, which shows 33, indicating that ECU has identified the idle condition according to the throttle voltage, and starts the idle control program accordingly.

Ye Sheng has idle status marker, throttle closed for YES.

At ordinary times, teachers can measure the voltage value of all kinds of electric injection system when the throttle is fully closed, so as to make a reference of idle voltage value when the car cannot be repaired into the system, which is generally in the range of a few zero volts to 1 volts.

It should be noted that a slightly concentrated air-fuel ratio at idle speed is beneficial to the stability of idle speed, while a consistently sparse ratio should be noted to have a greater impact on idle speed.

In general, on the data stream read by the detector, there should be no large deviation between the values. If there is an abnormal value, the reason should be investigated first. If the diagnostic instrument cannot enter the electric injection system, it is necessary to use a multimeter to conduct a preliminary check on whether the voltage value of each sensor is abnormal, or MSC super test lamp can be used to observe whether the sensor and actuator work normally.

The core component of the idle control valve is the stepping motor. If there is a problem with the idle valve, it is most likely that the stepping motor has a fault. It can be repaired by the following methods.