From the Service Bay: Finding an Oil Leak on a 2018 Audi Q5

An oil leak and an “add oil” message can leave a vehicle owner wondering where the oil is going—and what it will take to correct the problem.

The owner of this 2018 Audi Q5 Premium Plus returned to Charlie’s Foreign Car for an oil-leak recheck after an add-oil message appeared. Our inspection checked several potential leak sources before identifying the confirmed problem: a cracked, leaking oil pan.

What Charlie’s Foreign Car Checked

Oil can travel along engine surfaces before dripping, making the source difficult to identify from the wet area alone. That is why tracing the leak matters.

As part of this investigation, Charlie’s Foreign Car checked the following potential sources and confirmed passing results:

• Valve cover and cam cover seals: Checked for oil escaping from the upper engine area.
• Oil pan sealing surfaces: Checked for leakage at the pan’s sealing joints, separate from damage to the pan itself.
• Front and rear crankshaft seals: Checked for leakage around the crankshaft sealing areas. These seals, along with valve cover and oil pan seals, are established engine leak-repair areas.
• Oil filter cap, O-ring, and housing seals: Checked for leakage around the filter assembly. These seals help keep oil contained within the assembly.
• Oil drain plug and sealing area: Checked for leakage at the plug and its sealing surface. Damaged seals or threads can create leaks here.
• Timing cover sealing joints: Checked for oil escaping around the cover joints.
• Turbocharger oil supply and return lines: Checked for leakage at the lines and connections. Leaking oil pipes are a recognized turbocharger-related concern.
• Vacuum pump and associated seals: Checked for leakage in this area, another potential source of engine oil loss.

These areas passed inspection. The confirmed leak was traced to the oil pan itself.

What We Found

After cleaning the affected area and adding additional leak-detection dye, Charlie’s Foreign Car found a crack in the oil pan with an active leak.

Dye designed for engine-oil systems helps technicians trace escaping fluid during inspection. In this case, cleaning and further inspection helped distinguish the cracked pan from the other potential sources that had passed their checks.

The Repair Needed

The cracked oil pan required corrective work. According to the technician’s assessment, the subframe would need to be lowered to access and complete the oil-pan repair.

The diagnostic findings established the leak’s location and the access required. Confirmation of the completed oil-pan repair and its final retest remains separate from the passing inspections of the other components.

Why Checking the Other Sources Matters

Finding oil underneath an engine is only the beginning of an oil-leak diagnosis. Checking the surrounding components helps narrow the investigation and supports a repair recommendation based on the actual finding.

For this Audi, the other inspected sources passed, while the cracked oil pan provided a confirmed explanation for the external leak.

If your Audi develops an oil leak or displays an add-oil message, contact Charlie’s Foreign Car to schedule an inspection.