Consolidated fault analysis Crown car engine

        Symptom: a crown top car (92 models 3.OL GZS133), has traveled 250,000 km, fuel injector cleaning light after the car accelerated idling decreased from 750r / min 200r / min, and sometimes even destroy cars; hard acceleration exhaust pipe oil revenues have "bam" sound; when 20-4Okm / h fuel and oil revenues rear chassis has "Hang Hang" different sound.
        Failure Analysis: This car cleaned fuel injectors, oil flow, the fuel injection mercedes c3 quantity will increase in the same amount of fuel injection pulse width. Light step on the accelerator pedal, the engine ECU received a disconnect signal from the throttle position sensor idle contact, perception of the engine has been idling condition to transient condition. At this point, the engine ECU control the stepper motor type idle valve to return to the maximum opening position, while the throttle is opened, airflow through the throttle valve into the intake chamber, two aspects of the role of the intake indoor negative change. This change negative pressure sensor signal to the engine ECU, thereby increasing the amount of fuel injection to improve speed. The reason is because the failure occurs after cleaning fuel injectors, fuel injection is too large to make the mixture too thick, causing the car idling to reduce or even eliminate, maintenance is simple: the engine compartment on the right side there is a mixture adjustment valve, as long as there is exhaust gas analyzer under the circumstances, adjustment of the mixed can clip gas to the lean side (note: the adjustment must not too much so as not to affect the power output of the engine) that is changing the fuel injection pulse width, the fuel injection quantity is reduced, then the fault would eliminate the phenomenon.
        Oil revenues when hard acceleration, the exhaust pipe of "bam" sound, the cause of the failure above, that mixture is too thick or too small ignition energy, combustion in the cylinder can not fully residual unburned mixture combustion in the exhaust pipe, forming blasting. The maintenance method in two steps, first check the ignition timing and the spark plug, when the engine water temperature is normal, idle 750 ± 50r / min, a load to close the case, check the connection box shorting TE1-E1 terminal to check and adjust the ignition timing supreme BTDC 10 °; Second, under the correct ignition timing and spark a good case, dilute the mixture to adjust the valve to the side (Note: must not adjust too much, so as not to affect the engine power output).
        Speed ​​of 20-4Okm / h, the fuel and oil revenues, the rear of the chassis has "Hang Hang" sound. Fault location may drive carprog shaft, differential axle shaft, JZS133 type drive shaft for the triple crown sedan type shaft, soft-fit axle, should confirm the fault position and differential drive shaft connecting the first part of the opening, grip live gimbal rotation at one end and the other end, if clearance, replace the drive shaft, without clearance, inspection differential, hand holding and rotating flange, if free travel is too large there may be differential active and passive gear pinion backlash within the device is too large. If the differential without failure, the cause may be a gap between the axle and the ball is too large Cage.
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