MINI 3 cylinder inexplicably shaking and flameout-Troubleshooting_vehicles, vehicles

MINI 3 cylinder inexplicably shaking and flameout-Troubleshooting

September 15, 2024

There is a fault of abnormal jitter of a BMW Mini three-cylinder engine in the store. I am the third repair shop to take over. The fault phenomenon is that the red light vehicle occasionally shakes seriously or even stalls, and there is nothing abnormal when the vehicle starts again. Read the fault code and have the fault record of flameout. This vehicle has replaced the crankshaft pulley in the first store, replaced the injector, spark plug, the fault is still not solved, and the belt rotation is still a sub-factory goods, the original wheel is not broken, I do not know how many meanings. Car friends can not go to the 4S store repaired for a week and changed a set of fire, thought that the result just out of the 4S store 20 km fault appeared again. It means that the fault has not been eliminated. Under the introduction of a friend, the car friend found us. When I learned about the situation, I found that the work was not so easy. It took us a little more time to check the problem. It took us about 5 days to repair the problem. Because there was not much time during the day, we only found the fault point at night. Finally, we found the fault and succeeded in troubleshooting it. Share-do not reprint without the permission of the original work

Both of these minis are jitter faults, and the point of failure is unexpected.

First of all, we connected to the computer to read the fault records, and went to the test drive, and found that sometimes the jitter is really serious.

There is almost no need to check the vehicle jitter, and we need an oscilloscope to capture what happens to the engine in the event of a failure.

We connected the computer to the oscilloscope, and after a long test run, we found some faults that are invisible to the naked eye.

We found that the engine was sometimes very unstable and there was a serious fire.

At the same time of the failure, there was a serious shortage of air intake.

Two of the three MINI are challenging troubleshooting.

At night, we work overtime to continue to capture the frequency of the failure and the operation of each sensor and actuator in the event of a failure.

After several days of hard work, the suspected targets were ruled out one by one, getting closer and closer to the truth.

Spark plug removal

Fuel injector removal

We synthesize the data flow and the conditions under which the failure occurred, so we lock the target on the machine itself, and it takes a little courage to say that there is something wrong with the B38 machine itself. after all, the more meitative 4S stores dare not say that there is something wrong with the machine. we are about to prove whether our conclusion is correct by dismantling the engine.