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P2004AudiAudi A6 HubAll Audi P2004Medium Severity

P2004 on Audi A6

Intake Manifold Runner Control (IMRC) Stuck Open (Bank 1)

Factory diagnostic protocol and troubleshooting wire for fault code P2004 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
Drivable (Short Trip)
Medium urgency level
Est. Repair Cost
$150 - $600 (DIY: $40 - $180)
Parts & Labor DIY
Check P2004 On Another Audi Model:
Diagnose P2004 on Specific A6 Model Year:

1. Symptoms of P2004 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 P2004, drivers commonly observe:

Check Engine Light on on Audi A6 (3.0L Turbo V6 (A7/A8 S6 450HP) / 2.0L TFSI 261HP / 55 TFSI quattro)
Sluggish low-RPM acceleration and low-end torque loss on Audi A6 (3.0L Turbo V6 (A7/A8 S6 450HP) / 2.0L TFSI 261HP / 55 TFSI quattro)
Engine runs fine at high highway RPMs (3,500+ RPM) on Audi A6 (3.0L Turbo V6 (A7/A8 S6 450HP) / 2.0L TFSI 261HP / 55 TFSI quattro)
Slightly rough idle or minor intake whistling noise 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%
Carbon buildup binding the intake manifold swirl flap runner plates (Audi OEM Part)
25%
Broken plastic IMRC actuator linkage rod or vacuum diaphragm (Audi OEM Part)
12%
Faulty electronic IMRC runner control motor / solenoid (Audi OEM Part)
8%
Cracked vacuum line to IMRC actuator (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
Visually Inspect IMRC Actuator Linkage

Check the mechanical plastic linkage arms at the end of the intake manifold. Verify arms are not popped off or broken. on the Audi A6 equipped with 3.0L Turbo V6 (A7/A8 S6 450HP) / 2.0L TFSI 261HP / 55 TFSI quattro.

Required Tool: Flashlight, Mirror
02
Test Runner Flap Movement Manually

Move the runner lever by hand. It should spring back smoothly without binding or gritty resistance. on the Audi A6 equipped with 3.0L Turbo V6 (A7/A8 S6 450HP) / 2.0L TFSI 261HP / 55 TFSI quattro.

Required Tool: None
03
Test IMRC Solenoid / Actuator Motor

Command IMRC open and closed with bi-directional scan tool or check vacuum supply to diaphragm. 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 Bi-Directional Scanner or Vacuum Gauge
04
Clean Intake Manifold Carbon or Replace Actuator

Replace the broken linkage/actuator motor or remove manifold to clean heavy carbon deposits around the butterfly flaps. on the Audi A6 equipped with 3.0L Turbo V6 (A7/A8 S6 450HP) / 2.0L TFSI 261HP / 55 TFSI quattro.

Required Tool: Socket Set, Carburetor Cleaner, Gasket Set
05
Clear DTCs and Verify Runner Operation

Clear trouble codes and confirm low-end acceleration is restored. 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 (P2004)

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Direct-Fit Replacement Part

Audi A6 OEM Replacement Sensor

4.7 / 5.0 (Verified Fit)

Direct-fit replacement assembly engineered to OEM tolerances for Audi A6.

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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
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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 P2004 FAQs

What causes code P2004 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), P2004 is most frequently caused by Carbon buildup binding the intake manifold swirl flap runner plates or Broken plastic IMRC actuator linkage rod or vacuum diaphragm.

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 P2004?

Yes. Low-end engine torque will feel sluggish, but vehicle is drivable. Given that P2004 carries a Medium severity rating, we advise avoiding heavy towing or aggressive throttle inputs until sensor readings are verified.