0 1Turbocharger abnormal noise
[ Failure phenomenon ]: When Bora 1.8T accelerates to 3000 rpm, it emits a “humming” noise and the vehicle’s power is insufficient.
【solution】:
- The N75 solenoid valve is suspected to be faulty. When preparing to replace the valve, it was found that the vacuum tube connected to the solenoid valve was broken. After the broken vacuum tube was reconnected, the test run was removed;
- Summary: The vacuum tube connected to the booster pressure limiting solenoid valve N75 and the booster pressure unit is broken, causing the booster system pressure unit to fail to work when the boost pressure is higher than the normal range, so that the boost pressure sensor G31 detects a higher Pressure, this signal is transmitted to the engine control unit. The control unit generates the above-mentioned fault memory. Troubleshoot after repairing the broken vacuum tube.
02Noise when accelerating
[Solution ] : Remove the shield and hear the sound very clearly. Because the car has been driving for a long time, it is suspected that the exhaust pipe interface mat is damaged. After replacement, the exhaust branch pipe is still checked. The branch pipe mat was found and connected to the EGR system. The integrated valve connector is damaged, causing air leakage. After replacing the comprehensive valve connector, the fault is resolved.
03Intake pipe oil leaks
[Solution ] : The oil seal of the turbocharger leaks, so that the oil is discharged from the turbocharger and reaches the intake pipe. It has been tested that the ratio of oil consumption to gasoline consumption of the car exceeds the standard value, which is a quality problem of the turbocharger.
[Troubleshooting ] : Replace the turbocharger assembly.
04Exhaust gas recirculation valve
[Solution ] : At the beginning of the Bora car, the “burst” was very small, and then the “burst” sound became louder and louder. After careful inspection, it was found that the exhaust gas circulation valve plug was damaged: due to the relatively thin processing surface of the original plug, the perforation of the plug was generally damaged after 2 years or 20,000 km of driving. Because only the plug is damaged, it is more expensive to replace the new waste gas valve, and a plug is used for external processing.
05EPC alarm light on failure
[Solution ]:
- After testing, there are two fault codes in the Bora engine control unit: 16885 vehicle speed signal is unreliable and 16955 brake light switch-F unreliable signal. After clearing the fault code, the EPC light goes out. After several trial runs, the fault will be reappeared after driving for several hundred meters, all of which occur when the brake is pressed during driving, but there is only one fault code: the signal of the 16955 brake light switch is unreliable;
- Replace the brake light switch, and check the wiring from the brake light switch to the engine control unit, which is normal, and the fault has not been eliminated;
- After entering the engine control unit, come back for maintenance. During the maintenance process, the battery negative line was disconnected and connected again, and a similar phenomenon occurred in the control unit. The gasoline pump continued to work for about one minute and the throttle valve control system was abnormal.
- Connected to VAS5051 detection, the following fault code appears: 17967 Throttle valve control part J338 basic setting error; 17972 Throttle valve control part J338 voltage is insufficient at basic setting; 16955 Cruise / brake switch (A) circuit failure; 17953 Throttle valve control system error. It cannot be set, but the engine is running normally after starting. The above phenomenon has occurred in many tests;
- Solution After replacing the engine control unit, this phenomenon no longer occurs, and the throttle control part is basically set normally. After each matching of the control unit was performed, the test was repeated and no failure occurred. It was determined that the failure had been eliminated.
06 Odometer does not turn
[Solution ]: Whether the tooth is actively issued in the box, the disassembly inspection found that it was caused by water in the gear oil, because the oil and water mixed after the water entered, the plastic parts could not be well lubricated, and the heat was deformed and broken, causing the odometer to not turn. Replace with new parts, clean the gearbox and fill with new oil.
07 Brake trembling
[Solution ]: Generally, the new car runs to about 1000KM and the vehicle shakes on the brakes.
[Test process ] : 1. Remove the brake pads and brake discs and find that there are problems; 2. Replace the brake pads and brake discs, and troubleshoot; 3. Reappear the above phenomenon after driving about 1000KM. Troubleshooting: Replace the front wheel hub and brake Troubleshooting of discs and brake discs.