Whenever you are informed of irregular symptoms on your vehicle, you are right to be concerned, because a car represents a huge annual budget and unpredicted breakdowns don’t reduce the bill. So what if you feel as if you have a leaking injector on your Audi A4? You almost certainly figured it out thanks to black/oily drips along your engine, or a disturbed idle, or strange black smoke. These three symptoms are the main indicators of a leaking injector. As this troubles can produce more serious engine concerns on your car, we chose to compose this article to help you verify the failure of a leaking injector and deal with it properly. To achieve this, we will first take a look at the circumstance of gasoline injectors and then at those of diesel injectors Audi A4.
Leaking injector on my petrol Audi A4
It is crucial to know that the injectors on petrol and diesel engines are different, in reality, the difference in combustion between these two kind of engines makes the injection different. The key 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 Audi A4: The different leaks
It should be known that injector leaks on a Audi A4 equipped with a petrol engine are pretty rare. This is due to the much lower pressure in the petrol intake systems. Even so, there are two kind of leaks:
- Leakage from the top of the injector:
It is possible that you have a leak from the top of the injector, this is the portion that is connected to the fuel rail, an O-ring will be involved in this. - Leak injector of the lower part:
At last, you may experience a leak coming from the lower portion of the injector of your car, this one will appear from the junction with the engine and not with the rail as seen before.
Leaking injector on my diesel Audi A4
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 Audi A4: The different leaks
In the circumstance of leaking diesel injectors on your Audi A4, there are three different kind of leaks:
- Leakage from the injector inlet:
In this instance, it is an inlet pipe that will deform in the long run, in most cases the leak will be at the clamping point. - Injector return leakage:
As its name indicates, this leakage concerns the management of the fuel return in the injector, this time the injector that leaks on your Audi A4 will be a consequence 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 encounter an air noise and a compression loss. - If after verifying you have oil leaking but it does not come from your injectors, we recommend you to read this article on the existence of oil leaking on your Audi A4.
Leaking injector on my Audi A4, how to fix the leak
And finally, we’re going to take a look at how to fix a leaking injector on your car. Frequently a leak is associated, as we have seen prior to this, to a worn seal as a result of the pressures suffered. But think that the pressure in the circuit is monumental, specifically on diesel engines. So you will have to take some precautions:
- Lower the pressure before any work is achieved…
- Covering you to avoid the risk of fuel spillage
- NEVER work on a running diesel engine injector.
Regarding the repair part of your leak, it will regularly be restricted to changing the seals that have failed:
- Find out the source of the leak
- Dismantle 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 situations, these interventions are not necessarily complex, but if you have the tiniest hesitation in the treatment of your injector that leaks on your Audi A4, we recommend you to get closer to your auto technician to avoid any bad manipulation that could seriously harm the condition of your Audi A4.
Whenever you have any further questions about the Audi A4, do not hesitate to consult our Audi A4 category.
