Whenever you are aware of abnormal symptoms on your automobile, you are right to be preoccupied, because a car represents a massive annual budget and unpredicted breakdowns don’t lower the expenses. So what if you think that you have a leaking injector on your BMW 4 Series? You most likely figured it out thanks to black/oily drips along your engine, or a disturbed idle, or unusual black smoke. These three manifestations are the main signals of a leaking injector. As this troubles can lead to more critical engine concerns on your car, we made a decision to produce this content to help you ensure the failure of a leaking injector and deal with it properly. To do this, we will first of all look at the circumstance of gasoline injectors and then at those of diesel injectors BMW 4 Series.


Leaking injector on my petrol BMW 4 Series

It is essential to know that the injectors on petrol and diesel engines are distinct, in reality, the difference in combustion between these two sort of engines makes the injection distinct. The essential difference lies in the pressure experienced by the injectors, on a petrol engine it will vary between 3.5 bars for indirect injection and 120 bars for indirect injection.

Leaking injector on a petrol BMW 4 Series: The different leaks

It should be mentioned that injector leaks on a BMW 4 Series equipped with a petrol engine are rather infrequent. This is as a result of the much lower pressure in the petrol intake systems. Nevertheless, there are two sort of leaks:

  • Leakage from the top of the injector:
    It is conceivable that you have a leak from the top of the injector, this is the component that is linked to the fuel rail, an O-ring will be involved in this.
  • Leak injector of the lower part:
    At last, you may suffer a leak coming from the lower part of the injector of your car, this one will appear from the junction with the engine and not with the rail as seen previously.

Leaking injector on my diesel BMW 4 Series

Unlike petrol engines, which have spark combustion, diesel engines run on compression. This combustion system creates very high pressure in the engine, as do the injectors. On these models, the pressure is more than 10 times higher than on the direct injection of car petrol engines, reaching 1800 to 2000 bars.

Leaking injector on diesel BMW 4 Series: The different leaks

In the circumstance of leaking diesel injectors on your BMW 4 Series, there are three several sort of leaks:

  • Leakage from the injector inlet:
    In cases like this, it is an inlet pipe that will deform over time, commonly the leak will be at the clamping point.
  • Injector return leakage:
    As its name indicates, this leakage relates to the management of the fuel return in the injector, this time the injector that leaks on your BMW 4 Series will be the result of an O-ring or its plastic tip that leaks.
  • Injector base leak:
    This injection leak is one of the most bothersome, it is the junction between the engine and the injector nose that leaks at a copper seal, you should find an air noise and a compression loss.
  • If after verifying you have oil leaking but it does not come from your injectors, we encourage you to browse this content on the existence of oil leaking on your BMW 4 Series.

Leaking injector on my BMW 4 Series, how to fix the leak

And to finish, we’re going to look at how to fix a leaking injector on your car. Frequently a leak is linked, as we have seen prior to this, to a worn seal because of the pressures endured. But think that the pressure in the circuit is gigantic, specifically on diesel engines. So you will have to take some safety measures:

  • Lower the pressure before any work is completed…
  • Masking you to avoid the risk of fuel spillage
  • NEVER work on a running diesel engine injector.

Relating to the repair part of your leak, it will very often be restricted to swapping the seals that have failed:

  • Discover the source of the leak
  • Take apart the injector in question
  • Change the corresponding seal kit
  • Reassemble the assembly and tighten with a torque wrench in respect with the manufacturer’s standards.

In all cases, these interventions are not specifically very hard, but if you have the tiniest uncertainty in the treatment of your injector that leaks on your BMW 4 Series, we encourage you to get closer to your auto technician to avoid any bad manipulation that could seriously harm the condition of your BMW 4 Series.

If you have any additional questions about the BMW 4 Series, do not hesitate to consult our BMW 4 Series category.