2023 Audi A5 Problems: 3 Issues Every Owner Should Know
2023 model year · 0+ owner reports · Updated April 2026
According to Au7o's analysis of 0+ owner reports, the 2023 Audi A5 has 3 documented known issues. No issues are rated critical, indicating generally reliable ownership. Across all issues, repair costs range from $0 to $2,500. DIY maintenance guides at au7o.io.
All 3 Known Issues
On the 2008-2023 Audi A5, water pump failures are common across all A5 and S5 generations due to plastic impeller degradation and seal leaks. Audi uses plastic impellers that crack or disintegrate over time (typically 80,000-120,000 miles), causing coolant leaks and overheating. The water pump is timing belt/chain driven in many models, so replacement during timing service saves labor. Thermostat housings also crack from heat cycling, causing coolant leaks and erratic temperature readings. Symptoms include coolant puddles under the car, overheating in traffic, and temperature gauge fluctuations. Ignoring a failed water pump can cause severe engine overheating, warped cylinder heads, and blown head gaskets ($3,000-$5,000). The 3.0T S5 also has an electric auxiliary water pump for turbo cooling that fails separately.
Common Symptoms
- Coolant leak under front of car (pink/green puddle)
- Overheating in stop-and-go traffic or at idle
- Temperature gauge rising above normal (middle position)
- Coolant warning light or low coolant message
- No heat from cabin heater (auxiliary pump failure on S5)
- Hissing or gurgling noise from engine bay
- Steam or coolant smell from engine
How to Fix
Replace water pump AND thermostat together ($800-$1,500). Use OEM or high-quality aftermarket parts (Rein, Hepu, Meyle)—cheap pumps fail within 20k miles. If water pump is timing chain-driven, replace during timing service to save labor. Flush cooling system and refill with OEM Audi G12++ or G13 coolant (do NOT mix types). Inspect hoses and replace if cracked. S5 owners: Replace auxiliary electric water pump separately if heater fails ($300-$600). Monitor coolant level weekly and address leaks immediately.
What Owners Are Using
Parts and tips from 0+ owners who fixed this issue
- UpgradeUse latest OEM thermostat housing revision 06L121111P for Gen3, or Hepu P672 as a cost-effective German OEM-supplier alternative. (Genuine VW/Audi #06L121111P)
- UpgradeUSP Motorsports metal impeller upgrade kit eliminates the factory plastic impeller heat-deformation failure mode. (USP Motorsports #06L121111H-KT1)
- NoteAVOID Graf water pumps - multiple Audizine members report leaking from installation. Stick with OEM or Hepu.
- TipReplace water pump, thermostat housing, and union as a complete assembly. Also replace heater pipe O-ring N90365302 to prevent post-repair leaks.
On the 2008-2023 Audi A5, all direct-injection engines in the A5 and S5 (2.0 TFSI, 3.0T, and 3.2L V6) suffer from severe carbon buildup on intake valves. In direct-injection engines, fuel sprays directly into the cylinder, bypassing the intake valves. This means intake valves are only exposed to oil vapors from the PCV system, which bake onto the valve backs as hard carbon deposits. Over 60,000-100,000 miles, carbon restricts airflow, causing rough idle, misfires, hesitation, and power loss. The 3.0T supercharged S5 is particularly susceptible due to higher oil vapor pressure. In severe cases, carbon deposits prevent valves from seating properly, causing compression loss and valve damage. The ONLY effective fix is walnut blasting—blasting crushed walnut shells through the intake to remove carbon. A5OC forums recommend this as preventive maintenance every 60,000 miles.
Common Symptoms
- Rough or unstable idle (engine shakes at stoplights)
- Hesitation or stumbling on acceleration
- Reduced power and sluggish throttle response
- Poor fuel economy (2-4 MPG drop)
- Check engine light with misfire codes (P0300-P0306)
- Engine runs rough when cold, smooths out when warm
- Hard starting or extended cranking
How to Fix
WALNUT BLASTING: Remove intake manifold and blast crushed walnut shells through intake ports to remove carbon ($700-$1,200). Requires specialized equipment—DIY not recommended unless experienced. Dealers charge $1,200-$1,800; independent Audi shops charge less. Repeat every 60,000-80,000 miles as preventive maintenance. PREVENTION: Install catch can ($300-$500) to filter PCV oil vapors before they reach intake valves—extends cleaning interval to 100k+ miles. Add Liqui Moly Intake Valve Cleaner to every oil change ($15). Perform "Italian tune-up" monthly (spirited highway driving to high RPM).
What Owners Are Using
Parts and tips from 0+ owners who fixed this issue
- Upgrade034 Motorsport Catch Can Kit (034-101-1010) is the most complete prevention solution for B8/B8.5 A5 2.0T. Replaces factory PCV with billet aluminum breather plate. (034 Motorsport #034-101-1010)
- TipWalnut blasting every 40,000 miles is the community-recommended cleaning interval. DIY cost under $200 with Harbor Freight media blaster and walnut shell media.
- UpgradeMishimoto Baffled Oil Catch Can is a universal alternative if 034 kit is unavailable for your specific year. Requires custom bracket fabrication. (Mishimoto Baffled Oil Catch Can (Universal))
- NoteSymptoms include rough idle, misfires, and progressive power loss. By 60,000 miles, valves can be severely caked. Do not wait until symptoms are severe.
- TipAfter walnut blasting, install a catch can immediately to prevent rapid re-accumulation. Without a catch can, carbon will return to the same level within 30,000-40,000 miles.
On the 2017-2023 Audi A5, the B9 A5 (2017-2023) experiences various electrical gremlins, most commonly with the MMI infotainment system. The touchscreen freezes, reboots randomly, displays black screen, or becomes unresponsive. Owners also report interior trim rattles and squeaks from the dashboard, door panels, and center console. Other issues include backup camera failures, parking sensor malfunctions, wireless charging pad not working, and Android Auto/Apple CarPlay connectivity problems. Some models experience battery drain from parasitic draw. While frustrating, most electrical issues are minor annoyances rather than safety concerns. Audi issued software updates to address some infotainment bugs. A5OC forums report mixed results—some updates help, others don't. Build quality seems inconsistent across production runs.
Common Symptoms
- MMI touchscreen freezes or becomes unresponsive
- Infotainment system reboots randomly while driving
- Black screen on startup (system won't boot)
- Backup camera shows "No Signal" or black screen
- Rattling or creaking noises from dashboard/door panels
- Android Auto/Apple CarPlay disconnects randomly
- Wireless charging pad doesn't charge phone
- Battery dies after car sits for 3-4 days
How to Fix
Infotainment issues: Perform MMI hard reset (hold power + volume up for 10 seconds). If that fails, dealer can update software ($0-$150). Persistent issues may require MMI unit replacement ($1,500-$2,500). Interior rattles: Dealer can apply felt tape or foam to trim panels under warranty. Out-of-warranty DIY fixes involve removing panels and adding foam tape. Backup camera: Check for software update first, then camera replacement ($400-$800). Battery drain: Dealer performs parasitic draw test to identify faulty module. Android Auto/CarPlay: Use high-quality USB cable (cheap cables cause disconnects). For wireless charging, clean phone case and pad.
What Owners Are Using
Parts and tips from 0+ owners who fixed this issue
- TipFor MMI freezing and black screen issues, try a hard reset: hold the rotary power/volume knob for 30+ seconds until the system reboots. This resolves most temporary glitches.
- TipKeep MMI firmware updated through your Audi dealer or via the myAudi app. Many B9 infotainment bugs were addressed through software updates in 2019-2020.
- UpgradeVirtual Cockpit display failures require instrument cluster replacement. OEM refurbished units available from ECS Tuning at significant savings vs new from dealer ($800-$1,200 vs $2,000+). (Genuine VW/Audi Virtual Cockpit Instrument Cluster (Refurbished))
- NoteAftermarket stereo replacements void the warranty on the entire MMI system. If still under warranty, pursue dealer repair first.