Hello everyone, this is a column focusing on car repair and maintenance. There are car mysteries you don’t know, and it will teach you how to avoid the big pits on the road of car ownership. I believe that not only you but also many people have a certain sense of obscurity about the car aftermarket, which will help you uncover the unknown stories of car repair and maintenance.
In the field of automotive technology, there is a law that the more advanced technology is bound to bring a higher failure rate. Although turbocharging technology has been used for many years, even Japanese manufacturers who have never touched turbochargers have begun to use turbocharging technology in the past two years. But does this mean that turbocharging technology is really stable?
In this issue, the editor will take you to interpret: the common fault of BMW exhaust blue smoke, oil leakage more than oil lubrication pipe!
In front of this BMW three-Series recently encountered a strange thing, when the engine starts in the morning, the exhaust pipe will emit a puff of blue smoke (sometimes white and black smoke). Only a few seconds later, the smoke disappeared.
However, looking at the amount of oil, there is no obvious change.
If the engine burns oil, the oil must be missing, but the amount of oil in this engine has not changed much.
The editor has repaired hundreds of BMWs, and it is almost at a glance to see through this kind of problem. In fact, this engine is also burning oil, but it is only very slight. And the position of burning engine oil is the turbocharger which is most easily ignored by us.
Although BMW’s N20 engine has strong power, there are several common faults, and this kind of oil burning is the most typical one.
In order to remove the turbocharger, the exhaust pipe must be removed, the amount of work is not very large, but it will take more than an hour.
The turbocharger only removes the exhaust end, because the reason for burning the oil in the end is not on it, but a small tube on top of the turbocharger that flows oil.
Remove the turbocharger and you can see this small tubing, the yellowish one.
Because of the extremely high speed, no bearing can bear it, so the oil is used to lubricate the turbocharger, and that tubing is used to lubricate the turbocharger.
There are some design defects in this tubing, because the oil infiltrates the turbocharger for a long time, it will produce residue in the turbocharger over a long time. As soon as you start the engine, the oil will burn off with the exhaust, so you will see smoke in the exhaust pipe.
BMW also discovered the problem, so it specially produced improved tubing with an one-way valve to prevent excessive oil from flowing into the turbocharger.
The new tubing is relatively convenient to install, but it doesn’t take a few minutes at all. But it takes a lot of time to reset all the other accessories.
Of course, the removal of such an important part of the turbocharger must be subject to a road test. Road test is an indispensable step for the maintenance process inspection of the whole vehicle, because some problems will not be found at all in static state, and dynamic testing must be done to know whether there are assembly process problems in the car.
Many people may think that such a small amount of oil consumption does not seem to have much impact on the engine, but why do BMW manufacturers insist on producing improved tubing? There must be some reason behind it that you don’t know.
Is it okay if this tubing is not replaced?
There is nothing wrong with the normal consumption of oil, but if it is excessive, there will be a chain reaction. The excess oil goes into the exhaust pipe with the burning tail gas, and the ternary catalytic converter is right there. The falling sum in the oil will lead to poisoning of the ternary catalytic converter, and the ternary may be broken over a long period of time.
The three-way catalytic converter of a 100,000 yuan car is as expensive as one thousand yuan, and the three-way catalytic converter of a BMW is close to ten thousand yuan. Therefore, it is really impossible for this fault to be repaired. Otherwise, it would be a bit uneconomical to lose the big because of the small.
AdaAbbot 
4 
September 16, 2024 
