This bulletin provides information when there is increased oil consumption; >0.5ltr/1000 km.
full bulletin at NHTSA ↗2018 Audi Q5 engine problems
moderate Owners of the 2018 Audi Q5 have filed 13 NHTSA complaints about the engine at roughly $3,100 to repair (U.S. federal records, as of July 2026). Source: NHTSA Office of Defects Investigation. See engine across all vehicles →
Complaints
13
Recalls
0
Avg fix
$3,100
| Model year | engine complaints |
|---|---|
| 2014 Q5 | 29 |
| 2015 Q5 | 35 |
| 2016 Q5 | 27 |
| 2017 Q5 | 15 |
| 2018 Q5 (this page) | 13 |
| 2019 Q5 | 4 |
| 2020 Q5 | 3 |
| 2021 Q5 | 10 |
Is there a fix? Manufacturer service bulletins
The manufacturer has issued service bulletins covering engine on this vehicle — documented repair instructions, service campaigns, or warranty extensions sent to dealers. A TSB isn't a recall (it's not a free safety remedy), but it's the manufacturer acknowledging the issue and how to fix it.
This bulletin provides informaiton when the engine is not running smoothly, misfiring.
full bulletin at NHTSA ↗This bulletin provides information when DTC U140A00 Terminal 30 is stored in the ECM.
full bulletin at NHTSA ↗This bulletin provides information on VIN Plates, Safety Certification labels, and the ordering procedures.
full bulletin at NHTSA ↗This bulletin provides information on the use of the Audi frequencly analysis app, and where the application can be downloaded.
full bulletin at NHTSA ↗Source: NHTSA manufacturer communications. Bring the bulletin number to your dealer or shop.
The failure pattern owners describe
Owners report sudden, complete engine failures on 2018 Audi Q5s occurring as early as 34,000 miles and continuing through 72,000 miles. Failures include a cracked valve in a cylinder, a broken piston, and connecting rod bearing failure—all with zero prior warning. One owner at a busy intersection had the engine die while turning left with young children in the car. Another owner at 47,000 miles describes a piston breaking off inside the engine, causing total failure. A dealership technician stated this type of valve failure at 34,000 miles is extremely rare on normally maintained vehicles.
Beyond the catastrophic internal failures, owners report recurring cooling system problems: cracked coolant lines that fail twice after repair at 170,000 miles, a thermostat that sticks partially closed, water pump leaks, and thermostat housing leaks showing up at 43,000 miles. One owner notes the thermostat failure caused overheating and loss of RPM capability. A vehicle with an engine replacement by the previous owner had the check engine light come on just one month after the new owner purchased it.
Repair costs run $9,100 for head replacement, $11,000 to $15,000 for engine replacement. Audi's engine warranty stops at 50,000 miles—convenient timing for many of these failures. One owner mentions a fuel pump recall on other Audi models but not this one, and a warranty extension that was never claimed by the previous owner.
Same Audi Q5 engine reports on nearby years: 2015 · 2016 · 2017
Failure modes owners describe
Cracked/Chipped Valve
Internal valve failure in cylinder, typically identified as cracked or chipped. Narrative #1 reports a cracked/chipped valve in cylinder 3 diagnosed at a dealership after sudden engine malfunction.
When: 34,000 miles
Symptoms owners cite: Sudden loss of power; Multiple warning messages (drivetrain and system malfunction alerts); Vehicle became unstable and unsafe to operate
Repairs/costs cited: Cylinder head replacement estimated at $9,100 by Audi dealership
Broken Piston
Complete engine failure due to piston breakage inside the engine. Narrative #2 confirms total piston failure requiring engine replacement.
When: 47,000 miles
Symptoms owners cite: Engine died suddenly while turning left at intersection; Engine warning light flashed on dash; Engine would not restart after initial restart attempt
Repairs/costs cited: Complete engine failure; piston broken off
Cracked Coolant Line
Coolant line develops cracks causing repeated cooling system failures. Narratives #3 and #4 describe identical scenarios with recurring failures after multiple repair attempts.
When: 170,000 miles
Symptoms owners cite: Loss of automotive power; Warning message 'Shut off Engine, Check Cooling'; Engine temperature gauge elevated
Repairs/costs cited: Repaired twice at independent mechanics; failure reoccurred twice; dealer not contacted due to cost concerns
Recalls/TSBs owners mention: Manufacturer made aware of failure
Connecting Rod Bearing Failure
Connecting rod bearings fail inside engine, causing extensive internal damage. Narrative #5 documents bearing failure resulting in complete engine damage.
When: 49,000 miles
Symptoms owners cite: Abnormal vibration at 30 MPH; Engine Fault Detected message displayed; Vehicle stalled and unable to restart; Check engine warning light illuminated
Codes mentioned: Engine Fault Detected
Repairs/costs cited: Engine replacement required; vehicle not repaired
Engine Failure (Unspecified Internal Damage)
Complete engine failure requiring replacement. Narratives #6 and #7 report total engine failure without specific internal cause identified.
When: 55,000–72,000 miles
Symptoms owners cite: Engine stopped working; Abnormal sound from engine (Narrative #7); Loss of motive power
Repairs/costs cited: Engine replacement $11,000 plus labor $3,000–$4,000 (Narrative #6); no repair cost stated (Narrative #7)
Recalls/TSBs owners mention: Manufacturer made aware in Narrative #7
Thermostat Housing Leak
Thermostat housing develops coolant leaks. Narrative #10 reports leak at 43,000 miles; owner notes it is a known issue.
When: 43,000 miles
Symptoms owners cite: Coolant leak from thermostat housing
Repairs/costs cited: Identified during multi-point inspection; repair cost not stated
Recalls/TSBs owners mention: Owner notes it is a known issue that should be recalled
Thermostat Sticking and Water Pump Leak
Thermostat sticks partially closed and water pump develops leak simultaneously. Narrative #11 documents both failures together.
When: Mileage not stated
Symptoms owners cite: Check engine light illuminated
Codes mentioned: Thermostat sticking partially closed, Water pump leaking
Repairs/costs cited: Diagnosed at auto repair shop
Thermostat Failure Causing Overheat
Thermostat fails in closed position causing engine to overheat and lose RPM performance. Narrative #12 describes thermostat-induced overheating.
When: Mileage not stated
Symptoms owners cite: Engine overheat; Unable to reach required RPMs
Repairs/costs cited: Not stated
Water Pump Failure (Replacement Required)
Water pump requires replacement for cooling system function. Narrative #8 reports water pump failure requiring nearly $2,000 repair.
When: Mileage not stated; previous owner warranty extension mentioned but not claimed
Symptoms owners cite: Cooling system failure
Repairs/costs cited: Water pump replacement approximately $2,000
Recalls/TSBs owners mention: Fuel pump recalled on other models but not this one; warranty extension mentioned (Narrative #8)
Check Engine Light with No Root Cause Identified
Check engine light (MIL) illuminates on vehicle with engine replacement history. Narrative #9 reports MIL activation one month after purchase of vehicle with replaced engine.
When: 10,000 miles on replaced engine; occurred one month after purchase
Symptoms owners cite: Check engine light (MIL) illuminated
Repairs/costs cited: Previous owner had engine replaced; issue recurred on new owner
Synthesized from 13 NHTSA owner complaints — unverified consumer allegations, summarized for patterns. The verbatim filings appear below.
What owners are reporting 1 most recent
Vehicle: 2018 Audi Q5 Prestige Mileage: Approximately 34,000 miles On December 14, 2024, while driving at normal road speeds, my vehicle suddenly lost power and displayed multiple warning messages, including drivetrain and system malfunction alerts. The vehicle became unstable and unsafe to operate while I was in traffic, forcing me to carefully maneuver off the roadway. This occurred without…
Had engine trouble with your 2018 Audi Q5?
File a complaint with NHTSA → It's free, official, and how every report above got here — owner filings are the federal safety record this page is built on.
Common questions
How serious is the engine problem on the 2018 Audi Q5?
It's a documented issue but not catastrophic. 13 complaints have been filed. Repairs average $3,100 and most owners catch it before it causes a breakdown.
At what mileage does the engine typically fail?
Based on the 13 complaints filed, engine issues most often appear around 111,000 miles. Some report problems earlier; some make it well past 150,000 with no symptoms. Maintenance habits matter — vehicles that received timely fluid services and were not regularly overworked tend to last longer.
What does it cost to fix?
Independent shops typically charge around $3,100 for engine repairs on this vehicle. Dealer pricing tends to run 20-40% higher. The exact figure depends on the specific failure mode, parts availability, and your local labor rates. If you're outside factory warranty, an extended service contract often covers this category.
Are there any recalls related to engine?
No active recalls currently cover engine issues on this vehicle. The complaints filed represent owner-reported failures that haven't risen to the level of a manufacturer-issued recall — but they're still worth knowing about before you buy or budget for repairs.
Related
Complaint and recall data sourced from the National Highway Traffic Safety Administration (NHTSA)
public records database. Verify the raw federal record at
nhtsa.gov/vehicle/2018/Audi/Q5.
Severity ratings are derived from reported crashes, fires, injuries, and fatalities. Repair cost estimates are
independent-shop national averages and may differ in your area. Some links on this page are affiliate links.