2015 AUDI S5

Typical onset: 80,000-120,000 mi

Symptoms: Cold-start rattle for 2-3 seconds that worsens over time, Check engine light with cam/crank correlation codes (P000A, P000B), Metallic rattling from timing cover area, Catastrophic failure: sudden loss of power, severe engine noise, no-start

Fix: Timing chain service requires engine-out or significant front-end disassembly. Replace tensioners, guides, chains, and often cam adjusters. If caught late, stretched chain jumps teeth and valves meet pistons—then you're into head gaskets, bent valves, or complete engine rebuild. Preventive service: 12-16 hours labor. Post-failure rebuild: 40-60+ hours.

Estimated cost: $3,500-6,000 preventive / $12,000-18,000 post-failure engine rebuild

Typical onset: 60,000-90,000 mi

Symptoms: Rough idle, especially when cold, Misfires under load or acceleration, Loss of power and throttle response, Check engine light with misfire codes (P0300-P0306)

Fix: Walnut blasting the intake valves is the only real fix. Remove intake manifold and supercharger, media-blast each port. 6-8 hours labor. This is a maintenance item on direct-injection Audis, not a one-and-done repair. Expect to repeat every 60-80k miles.

Estimated cost: $800-1,400

Typical onset: 70,000-110,000 mi

Symptoms: Transmission fluid leak under vehicle, typically passenger side, Low trans fluid warning on dash, Delayed or harsh shifts if fluid level drops, Pink fluid pooling after parking

Fix: Replace cooler and/or lines, flush contaminated coolant if cooler failed internally and mixed fluids. Trans service recommended at same time. 3-5 hours labor depending on access and whether you're replacing just lines or full cooler assembly.

Estimated cost: $600-1,200

Typical onset: 60,000-100,000 mi

Symptoms: Clunking when shifting from Park to Drive or Reverse, Vibration or shudder during acceleration, Excessive drivetrain movement visible when revving in Park

Fix: Replace the upper transmission mount (dogbone mount). Simple job, 1-2 hours labor. Often done alongside engine mounts if those are also worn.

Estimated cost: $300-500

Typical onset: 90,000-130,000 mi

Symptoms: Whining or squealing noise from engine bay, RPM-dependent, Noise changes pitch with throttle input, Loss of boost if clutch fully fails, Check engine light with underboost codes (P0299)

Fix: Supercharger must be removed and rebuilt or replaced. Clutch bearing and nose cone rebuild: 8-10 hours labor. Aftermarket rebuild kits available, or send unit out for professional rebuild. Full supercharger replacement if internals are damaged.

Estimated cost: $2,000-3,500 rebuild / $4,000-6,000 replacement

Typical onset: 50,000-90,000 mi

Symptoms: Excessive oil consumption (1 qt per 1,000-2,000 miles), White smoke from exhaust on startup or deceleration, Rough idle and sluggish throttle response, Oil in intake tract or intercooler

Fix: Replace PCV valve, breather hoses, and oil separator integrated into valve cover. Sometimes requires both valve covers if oil contamination is severe. 4-6 hours labor. Often combined with carbon cleaning since intake is already apart.

Estimated cost: $800-1,500