2018 Audi S4 Turbocharger Intercooler Tube Replacement Cost

Vehicles with turbocharged induction engines have the option to cool the air being compressed by the turbocharger, and this is done by diverting compressed, filtered inlet air through an intercooler before it is pushed into the intake manifold. The cooler temperatures provided by the intercooler allow the engine to use more fuel per combustion event, making more power on demand. The intercooler is fed by intercooler piping, which also carries air from the intercooler to the intake manifold. Typically, an intercooler tube will be used as the final stage of delivery for the air as it moves to the intake manifold. This is because the tube may need to be flexible or form-fitted, and is typically non-metallic.

As the final stage of boost pressure delivery from the turbocharger to the intake manifold, the intercooler tube should deliver relatively cool air from the intercooler to the intake manifold via the throttle body. Since this tube is not under high heat and must route through other components to arrive at the throttle body, it is typically plastic or a rubber composite material, and will likely be molded to fit directly between components yet prevent limiting airflow. This is also commonly the mounting location for the boost pressure sensor.

Underboost issues are the only issue to consider when the intercooler tube cracks or becomes disconnected. Boost leaks occur in these situations, and the intended amount of compressed air will not arrive at the engine. There may also be an issue with the engine running a rich air to fuel ratio, and the check engine light will illuminate to denote these errors. Lastly, low engine power may be noticed, depending on the size of the leak.