Misfires can occur due to faulty spark plugs, ignition coils, or fuel injectors.

Some Audi engines, particularly the V6, may consume more oil than expected, leading to frequent top-ups.

Timing chain tensioners can fail, causing rattling noises and potential engine damage if not addressed.

Direct injection engines are prone to carbon build-up on intake valves, which can affect performance and efficiency.

Turbocharged engines may face issues with the turbocharger, including failure or oil leaks.

Coolant leaks can occur from various parts of the engine, such as the water pump or radiator, leading to overheating.

Various sensors (oxygen sensor, MAF sensor) can fail, leading to poor engine performance and check engine lights.

Components related to emissions control systems (EGR valve, catalytic converter) can fail, affecting emissions and performance.

Dynamic Brake Support (DBS) systems, while high-tech, can sometimes malfunction due to sensor issues, software glitches, or wiring problems, leading to unintended braking or failure to activate when needed.

V-shaped engines, like the V6 in this Audi S4, can suffer from engine misfires due to faulty spark plugs, ignition coils, or fuel injectors, leading to rough idling and poor acceleration.

The 2019 Audi S4's V6 engine is turbocharged, and turbocharger issues such as oil leaks, worn bearings, or boost pressure loss can result in reduced power and increased fuel consumption.

Direct injection engines, like the one in this Audi S4, are prone to carbon buildup on intake valves, which can cause poor engine performance and reduced fuel efficiency.

The complex emissions systems needed to meet Tier 3 BIN 70 LEV3 ULEV70 standards can sometimes fail, leading to increased emissions, check engine lights, and the need for costly repairs.

Audi V6 engines are known for timing chain issues, which can result in a rattling noise, poor engine performance, and potentially catastrophic engine damage if not addressed.

The high-performance nature of the Audi S4's engine means that cooling system components like radiators, water pumps, and thermostats are under high stress and can fail, leading to overheating.

Some Audi V6 engines have been known to consume oil at higher rates than expected, which can lead to frequent top-offs and potential engine damage if oil levels are not maintained.

Issues with the high-pressure fuel pump or fuel injectors can lead to poor engine performance, starting difficulties, and reduced fuel efficiency.

Modern vehicles like the 2019 Audi S4 have complex electrical systems that can suffer from issues such as faulty wiring, failing sensors, or software malfunctions, leading to a range of engine performance problems.

Dynamic Brake Support (DBS) systems, while high-tech, can sometimes malfunction due to sensor issues, software glitches, or wiring problems, leading to unintended braking or failure to activate when needed.

V-shaped engines, like the V6 in this Audi S4, can suffer from engine misfires due to faulty spark plugs, ignition coils, or fuel injectors, leading to rough idling and poor acceleration.

The 2019 Audi S4's V6 engine is turbocharged, and turbocharger issues such as oil leaks, worn bearings, or boost pressure loss can result in reduced power and increased fuel consumption.

Direct injection engines, like the one in this Audi S4, are prone to carbon buildup on intake valves, which can cause poor engine performance and reduced fuel efficiency.

The complex emissions systems needed to meet Tier 3 BIN 70 LEV3 ULEV70 standards can sometimes fail, leading to increased emissions, check engine lights, and the need for costly repairs.

Audi V6 engines are known for timing chain issues, which can result in a rattling noise, poor engine performance, and potentially catastrophic engine damage if not addressed.

The high-performance nature of the Audi S4's engine means that cooling system components like radiators, water pumps, and thermostats are under high stress and can fail, leading to overheating.

Some Audi V6 engines have been known to consume oil at higher rates than expected, which can lead to frequent top-offs and potential engine damage if oil levels are not maintained.

Issues with the high-pressure fuel pump or fuel injectors can lead to poor engine performance, starting difficulties, and reduced fuel efficiency.

Modern vehicles like the 2019 Audi S4 have complex electrical systems that can suffer from issues such as faulty wiring, failing sensors, or software malfunctions, leading to a range of engine performance problems.