In cases where you are aware of irregular symptoms on your automobile, you are right to be concerned, because a car represents a big annual budget and unforeseen malfunctions don’t reduce the costs. So what if you sense that you have a leaking injector on your Audi S4? You most likely figured it out thanks to black/oily drips along your engine motor, or a troubled idle, or strange black smoke. These three manifestations are the main symptoms of a leaking injector. As this problem can bring on more critical engine complications on your car, we thought we would write this article to help you verify the failure of a leaking injector and handle it properly. To do so, we will initially look at the circumstance of gasoline injectors and then at those of diesel injectors Audi S4.
Leaking injector on my petrol Audi S4
It is vital to know that the injectors on petrol and diesel engines are different, the truth is, the difference in combustion between these two kind of engines makes the injection different. The key difference lies in the pressure undergone 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 S4: The different leaks
It should be known that injector leaks on a Audi S4 equipped with a petrol engine are rather infrequent. This is caused by the much lower pressure in the petrol intake systems. Nevertheless, 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:
Finally, 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 Audi S4
Unlike petrol engines, which have spark combustion, diesel engines run on compression. This combustion procedure produces 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 S4: The different leaks
In the circumstance of leaking diesel injectors on your Audi S4, there are three different kind 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 implies, this leakage concerns the management of the fuel return in the injector, this time the injector that leaks on your Audi S4 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 troublesome, 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 checking you have oil leaking but it does not come from your injectors, we advise you to browse this article on the existence of oil leaking on your Audi S4.
Leaking injector on my Audi S4, how to fix the leak
And to finish, we’re going to look at how to fix a leaking injector on your car. Very often a leak is associated, as we have seen prior to this, to a worn seal as a result 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 precautions:
- 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.
Regarding the repair part of your leak, it will frequently be limited to swapping the seals that have failed:
- Locate 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 situations, these interventions are not necessarily difficult, but if you have the smallest hesitation in the treatment of your injector that leaks on your Audi S4, we advise you to get closer to your motor mechanic to avoid any bad manipulation that could significantly harm the condition of your Audi S4.
If perhaps you have any further questions about the Audi S4, do not hesitate to consult our Audi S4 category.
