P2004 fault code: what it means

P2004: Bank 1 intake manifold runner (swirl / tumble) flaps stuck open.

Engine and gearbox (powertrain) · Minor

Usual causes, most likely first

broken runner flaps or linkage
faulty runner control actuator
carbon build-up on the flaps

P2004 by make

Audi

Intake manifold flaps stuck open on bank 1. Common on 2.0 TFSI; on 2012-2016 3.0 TFSI the vacuum water pump can draw too much vacuum.

Usual causes: intake manifold flap binding or sticking; vacuum leak (3.0 TFSI: vacuum water pump hose layout); runner position sensor (G336); ECU software / updated manifold needed

Mercedes-Benz

Intake runner/swirl flap stuck open, bank 1. On M272/M273 petrols the plastic flap lever breaks; on OM642 diesels carbon jams the swirl flaps.

Usual causes: broken intake manifold flap lever (M272/M273); carbon build-up on swirl flaps (OM642); failed flap actuator/motor

Skoda

Intake manifold flaps stuck open on bank 1. Common on 2.0 TFSI/TSI.

Usual causes: intake manifold flap binding or sticking; vacuum leak; runner position sensor (G336); ECU software / updated manifold needed

Volkswagen

Intake manifold flaps stuck open on bank 1. Common on 2.0 TFSI/TSI.

Usual causes: intake manifold flap binding or sticking; vacuum leak; runner position sensor (G336); ECU software / updated manifold needed

Volvo

Intake manifold runner (swirl flap) stuck open, bank 1.

Usual causes: carbon-seized swirl flaps; failed swirl actuator; broken linkage

What the repair usually costs

Water pump replacement (belt-driven, not behind timing cover)NZ$340–NZ$770 · A$340–A$760
Water pump with timing belt kit (timing-belt-driven pump)NZ$770–NZ$1,970 · A$780–A$1,970
Water pump inside timing cover (chain engine)NZ$980–NZ$2,100 · A$1,020–A$2,160
Intake valve carbon clean (walnut blast, direct injection)NZ$530–NZ$1,190 · A$560–A$1,240

Not sure what P2004 means on your car? Ask Credov.

Before you clear it

Write the code down or photograph the scanner first. A code that comes straight back after clearing points to a fault that is still there. A car whose codes were cleared just before you arrived may be hiding one: the scanner's readiness monitors show "not ready" for a while after codes are cleared.

Researched by Credov from manufacturer and workshop sources. A fault code points to where a fault may be; a workshop confirms it with a diagnosis. Browse all fault codes.