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P0457AudiAudi Q5 HubAll Audi P0457Low Severity

P0457 on Audi Q5

EVAP System Leak Detected (Fuel Cap Loose/Off)

Factory diagnostic protocol and troubleshooting wire for fault code P0457 specifically for the Audi Q5 (2020–2026, 2.0L TFSI Turbo / 3.0L Turbo V6 (SQ5 349HP) / 55 TFSI e PHEV).

Verified OEM Telemetry & Field Repair Tree
Audi Q52020–2026
Audi Q5
SUV2.0L TFSI Turbo / 3.0L Turbo V6 (SQ5 349HP) / 55 TFSI e PHEV
Reliability
Sensor Voltage Ref
0.1V – 5.0V Ref
Q5 SAE Mode $01
ECU Network Bus
500 kbps CAN-FD
ISO 15765-4 Compliant
Drivability Status
Drivable (Short Trip)
Low urgency level
Est. Repair Cost
$0 - $120 (DIY: $0 - $30)
Parts & Labor DIY
Check P0457 On Another Audi Model:
Diagnose P0457 on Specific Q5 Model Year:

1. Symptoms of P0457 on Audi Q5

When the Engine Control Module (ECM/PCM) on your Audi Q5 (2.0L TFSI Turbo / 3.0L Turbo V6 (SQ5 349HP) / 55 TFSI e PHEV) logs fault code P0457, drivers commonly observe:

'CHECK FUEL CAP' message in dash display on Audi Q5 (2.0L TFSI Turbo / 3.0L Turbo V6 (SQ5 349HP) / 55 TFSI e PHEV)
Illuminated Check Engine Light on Audi Q5 (2.0L TFSI Turbo / 3.0L Turbo V6 (SQ5 349HP) / 55 TFSI e PHEV)
Slight gasoline vapor odor near fuel door on Audi Q5 (2.0L TFSI Turbo / 3.0L Turbo V6 (SQ5 349HP) / 55 TFSI e PHEV)
Audi Q5 OBD-II Port Location
The 16-pin diagnostic connector is located Left side under driver steering column. Plug in your scan tool to verify freeze-frame sensor values.

2. Most Likely Causes on Audi Q5

Historical warranty claims and technical repair bulletins for Audi Q5 point to the following failure distribution:

55%
Loose, unclicked, or forgotten gas cap (Audi OEM Part)
25%
Cracked, dried out, or missing rubber O-ring gasket on fuel cap (Audi OEM Part)
12%
Cracked filler neck neck where gas cap seals (Audi OEM Part)
8%
Faulty EVAP fuel tank pressure sensor (FTP) (Audi OEM Part)
* Source: Synthesized from NHTSA ODI field repair telemetry and verified OEM Technical Service Bulletin (TSB) repair tree frequency percentiles for Audi Q5.

3. Step-by-Step DIY Repair Guide for Audi Q5

01
Inspect and Tighten Gas Cap

Unscrew gas cap, inspect rubber seal for cracks, reinstall and turn until it clicks firmly 3 times. on the Audi Q5 equipped with 2.0L TFSI Turbo / 3.0L Turbo V6 (SQ5 349HP) / 55 TFSI e PHEV.

Required Tool: None
02
Inspect Fuel Filler Neck Lip

Check the metal filler neck lip for rust, grit, or dings preventing a tight seal. on the Audi Q5 equipped with 2.0L TFSI Turbo / 3.0L Turbo V6 (SQ5 349HP) / 55 TFSI e PHEV.

Required Tool: Clean Rag
03
Replace Gas Cap with OEM Replacement

If rubber gasket is flattened or hardened, buy a factory OEM gas cap. on the Audi Q5 equipped with 2.0L TFSI Turbo / 3.0L Turbo V6 (SQ5 349HP) / 55 TFSI e PHEV.

Required Tool: OEM Gas Cap
04
Clear Trouble Code or Drive

Clear DTCs with scanner, or drive vehicle for 3–5 days until the PCM runs an overnight EVAP vacuum decay test and turns off the light automatically. on the Audi Q5 equipped with 2.0L TFSI Turbo / 3.0L Turbo V6 (SQ5 349HP) / 55 TFSI e PHEV.

Required Tool: OBD-II Scanner
Recommended Parts & Testing Tools

Equipment for Diagnosing Audi Q5 (P0457)

Prime Fast Delivery & Verified Fitment
EVAP Seal Replacement

OEM Tethered Fuel Gas Cap with O-Ring

4.7 / 5.0 (Direct Fit)

Tight-sealing factory fuel cap resolves common EVAP small/large leak codes without workshop visits.

$17 – $26 Prime
Check Fitment on Amazon
Sensor Signal Voltage Meter

AstroAI Auto-Ranging Digital Multimeter

4.6 / 5.0 (Best Seller)

Essential for testing 0.1V–5.0V sensor reference signals, ground continuity (<0.20Ω), and harness resistance.

$29.99 Prime
View on Amazon
Top Mobile OBD-II Scanner

BlueDriver Bluetooth Pro OBDII Scan Tool

4.7 / 5.0 (50,000+ Reviews)

Reads and clears enhanced codes (ABS, Airbag, Transmission, Engine) & live freeze-frame telemetry on phone.

Compare OEM & Aftermarket Replacement Sensors for Audi Q5Verified direct-fit pricing from Denso, Bosch, Motorcraft, and ACDelco on Amazon.
Find Parts on Amazon
* As an Amazon Associate, MazicBay earns from qualifying purchases. Prices & availability subject to change.

Other Common Fault Codes on Audi Q5

Frequently diagnosed powertrain, emissions, and sensor trouble codes logged on the Audi Q5:

4. Audi Q5 P0457 FAQs

What causes code P0457 to trigger on a Audi Q5?

On the Audi Q5 (2.0L TFSI Turbo / 3.0L Turbo V6 (SQ5 349HP) / 55 TFSI e PHEV), P0457 is most frequently caused by Loose, unclicked, or forgotten gas cap or Cracked, dried out, or missing rubber O-ring gasket on fuel cap.

Where is the OBD-II port located on my Audi Q5?

On the Audi Q5, the 16-pin DLC diagnostic connector is located Left side under driver steering column. Plug in any standard OBD-II scanner with the ignition in the ON position to read freeze-frame parameters.

Can I safely drive my Audi Q5 with code P0457?

Yes. Safe to drive indefinitely, but fuel vapors escape into the atmosphere. Given that P0457 carries a Low severity rating, we advise avoiding heavy towing or aggressive throttle inputs until sensor readings are verified.