Checking and adjusting the position of the K-Jetronic, KE-Motronic flow meter flap (VW Passat B3)

The air flow meter flap deflects to a greater or lesser extent depending on the amount of air entering the engine. If the flap rest position is too low, the engine cannot be started. In addition, if the flap rest position is incorrectly adjusted, difficulties arise when starting a hot engine and malfunctions occur during transient processes.

Checking the resting position

Warm up the engine until the oil temperature is at least +50°C.

Remove the central high-voltage wire from the ignition distributor and short it to ground.

Attention: When turning on the starter, do not hold the wire with your hands, see chapter "Ignition system".

Remove the air intake guide shroud.

Turn on the starter for about 10 seconds.



K-Jetronic: The upper edge of the air flow meter flap must be at the point indicated by the arrow, or a maximum of 0.5 mm below the edge of the diffuser cone.

KE-Motronic: The upper edge of the air flow meter flap must be 1.9-3.0 mm below the edge of the diffuser cone, otherwise adjust the rest position.

Adjusting the resting position

Lift the flow meter flap with your fingers.



K-Jetronic: Adjust the position of the air flow meter flap by carefully bending the retaining wire clip (arrow).



KE-Motronic: Adjust the position of the air flow meter flap using the adjusting screw (arrow).

Caution: Do not damage the flow meter socket. Do not bend the leaf spring.

Install the air intake guide cover, connect the high voltage wire.

Finally, adjust the engine idle speed and CO content.