Intake manifold switchover, function engine 272 - GF07.61-P-3028V

ENGINE 272.942 in MODEL 171 

ENGINE 272.963 in MODEL 171 

Shown on ENGINE 272 

With the intake manifold switchover, switching between a long or a short intake route is possible. For this purpose, a longitudinal switch flap is located in the intake manifold for each cylinder. The longitudinal switch flaps for each cylinder bank are actuated by an aneroid capsule and a flap shaft. Both aneroid capsules are connected by a vacuum line.

The variable intake manifold switchover valve is connected in series in the vacuum line to the aneroid capsules.

Short intake route (without actuation) 

The variable intake manifold switchover valve is de-energized and the aneroid capsules are ventilated. Without actuation, the length switch flaps by spring force and free up the short intake route.

Long intake route 

If the variable intake manifold switchover valve is actuated by a ground signal from the ME control unit, vacuum pressure from the vacuum memory enters the aneroid capsules. The flap shafts are operated and the length switch flaps close.

Under the following conditions, the long intake route is selected:

• Engine load more than approx. 50%.
• Engine speed lower than 3500 rpm

Only an intake manifold switchover aneroid capsule is installed for engine 273. The two flap shafts are combined in the intake manifold.

Component description for the ME-SFI [ME] control unit	GF07.61-P-6000V
Component description for the variable intake manifold switchover valve	GF09.20-P-6001V
Component description for the intake manifold	GF09.20-P-6010V
Component description for the crankshaft Hall sensor	GF07.04-P-6220V
Component description for the hot film MAF sensor	GF07.07-P-6000V
Component description for the throttle valve actuator	GF30.20-P-2020V