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P0351AudiAudi A6 HubAll Audi P0351Critical Severity

P0351 on Audi A6

Ignition Coil A Primary/Secondary Circuit Malfunction

Factory diagnostic protocol and troubleshooting wire for fault code P0351 specifically for the Audi A6 (2020–2026, 3.0L Turbo V6 (A7/A8 S6 450HP) / 2.0L TFSI 261HP / 55 TFSI quattro).

Verified OEM Telemetry & Field Repair Tree
Audi A62020–2026
Audi A6
Sedan3.0L Turbo V6 (A7/A8 S6 450HP) / 2.0L TFSI 261HP / 55 TFSI quattro
Reliability
Sensor Voltage Ref
0.1V – 5.0V Ref
A6 SAE Mode $01
ECU Network Bus
500 kbps CAN-FD
ISO 15765-4 Compliant
Drivability Status
Not Recommended
Critical urgency level
Est. Repair Cost
$100 - $350 (DIY: $30 - $90)
Parts & Labor DIY
Check P0351 On Another Audi Model:
Diagnose P0351 on Specific A6 Model Year:

1. Symptoms of P0351 on Audi A6

When the Engine Control Module (ECM/PCM) on your Audi A6 (3.0L Turbo V6 (A7/A8 S6 450HP) / 2.0L TFSI 261HP / 55 TFSI quattro) logs fault code P0351, drivers commonly observe:

Flashing Check Engine Light on Audi A6 (3.0L Turbo V6 (A7/A8 S6 450HP) / 2.0L TFSI 261HP / 55 TFSI quattro)
Severe engine shuddering and jerking under acceleration on Audi A6 (3.0L Turbo V6 (A7/A8 S6 450HP) / 2.0L TFSI 261HP / 55 TFSI quattro)
Hard misfire on Cylinder 1 (accompanied by P0301) on Audi A6 (3.0L Turbo V6 (A7/A8 S6 450HP) / 2.0L TFSI 261HP / 55 TFSI quattro)
Strong smell of unburned gasoline from exhaust on Audi A6 (3.0L Turbo V6 (A7/A8 S6 450HP) / 2.0L TFSI 261HP / 55 TFSI quattro)
Audi A6 OBD-II Port Location
The 16-pin diagnostic connector is located Driver lower dash trim near parking brake assembly. Plug in your scan tool to verify freeze-frame sensor values.

2. Most Likely Causes on Audi A6

Historical warranty claims and technical repair bulletins for Audi A6 point to the following failure distribution:

55%
Failed ignition coil pack on Cylinder 1 (Coil A) (Audi OEM Part)
25%
Broken or melted wiring harness to ignition coil 1 (Audi OEM Part)
12%
Corroded or broken terminal pins in coil electrical connector (Audi OEM Part)
8%
Burned ignition driver transistor (IGBT) inside the ECM/PCM (Audi OEM Part)
* Source: Synthesized from NHTSA ODI field repair telemetry and verified OEM Technical Service Bulletin (TSB) repair tree frequency percentiles for Audi A6.

3. Step-by-Step DIY Repair Guide for Audi A6

01
Locate Coil A (Cylinder 1 Ignition Coil)

Identify Cylinder 1 ignition coil pack mounted on the valve cover. on the Audi A6 equipped with 3.0L Turbo V6 (A7/A8 S6 450HP) / 2.0L TFSI 261HP / 55 TFSI quattro.

Required Tool: Flashlight
02
Perform Coil Swap Test

Swap Coil 1 with Coil 2. Clear codes and restart engine. If code switches to P0352 (Coil B), the ignition coil is 100% defective. on the Audi A6 equipped with 3.0L Turbo V6 (A7/A8 S6 450HP) / 2.0L TFSI 261HP / 55 TFSI quattro.

Required Tool: 10mm Socket, Ratchet, OBD-II Scanner
03
Test Wiring Harness if Code Remains P0351

Check for 12V battery power, chassis ground, and 5V trigger pulse from the PCM on the 3-pin / 4-pin harness plug. on the Audi A6 equipped with 3.0L Turbo V6 (A7/A8 S6 450HP) / 2.0L TFSI 261HP / 55 TFSI quattro.

Required Tool: Digital Multimeter, Test Light
04
Replace Ignition Coil & Spark Plug

Install a new OEM ignition coil (e.g. Denso, Motorcraft, Delphi) and replace the spark plug on Cylinder 1. on the Audi A6 equipped with 3.0L Turbo V6 (A7/A8 S6 450HP) / 2.0L TFSI 261HP / 55 TFSI quattro.

Required Tool: 5/8 Spark Plug Socket, 10mm Socket, Ratchet
05
Clear Trouble Codes and Road Test

Clear DTCs and verify smooth acceleration under load. on the Audi A6 equipped with 3.0L Turbo V6 (A7/A8 S6 450HP) / 2.0L TFSI 261HP / 55 TFSI quattro.

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

Equipment for Diagnosing Audi A6 (P0351)

Prime Fast Delivery & Verified Fitment
OEM Ignition Component

Direct-Fit Laser Iridium Spark Plugs (Set of 4/6)

4.8 / 5.0 (Top Rated)

Pre-gapped iridium spark plugs engineered to restore smooth combustion on Audi A6.

$36 – $68 Prime
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Ignition Service Tool

Magnetic Swivel Spark Plug Socket Set

4.8 / 5.0 (Amazon Choice)

360-degree magnetic swivel socket prevents ceramic plug cracks inside deep engine spark wells.

$16.99 Prime
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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 A6Verified direct-fit pricing from Denso, Bosch, Motorcraft, and ACDelco on Amazon.
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Other Common Fault Codes on Audi A6

Frequently diagnosed powertrain, emissions, and sensor trouble codes logged on the Audi A6:

4. Audi A6 P0351 FAQs

What causes code P0351 to trigger on a Audi A6?

On the Audi A6 (3.0L Turbo V6 (A7/A8 S6 450HP) / 2.0L TFSI 261HP / 55 TFSI quattro), P0351 is most frequently caused by Failed ignition coil pack on Cylinder 1 (Coil A) or Broken or melted wiring harness to ignition coil 1.

Where is the OBD-II port located on my Audi A6?

On the Audi A6, the 16-pin DLC diagnostic connector is located Driver lower dash trim near parking brake assembly. 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 A6 with code P0351?

No. Cylinder 1 ignition coil has failed completely, causing an active misfire and dumping unburned fuel into the catalytic converter. Given that P0351 carries a Critical severity rating, we advise avoiding heavy towing or aggressive throttle inputs until sensor readings are verified.