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The 2.4 multiair part is expensive and the special tool needed to replace it is even more expensive. Then you have to get oil in it so the engine will start. Some have done it if you search.
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This is an old thread about that:
Apparently it takes a lot of cranking. Perhaps consider pulling the fuel pump fuse to prevent too much fuel in the combustion chambers.
 

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09 - Engine, 2.4L Multiair / Cylinder Head / ASSEMBLY, Variable Valve Actuation / Operation

OPERATION

Variable valve actuation controls the operation of the intake valves. By using a hydraulic link between the camshaft and the intake valves, the valve lift and timing can be adjusted infinitely.

The main components of variable valve actuation are the Powertrain Control Module (PCM) programming and the variable valve actuation module. The variable valve actuation module contains one set of the following components for each cylinder:

•Upper Pumping Element (3)
•Solenoid Valve (1)
•Hydraulic Brake Pumping Element/Hydraulic Lash Adjusters (2)
•Oil Accumulator (4)
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The upper pumping elements (1) in the variable valve actuator are filled with oil from the engine lubrication system. The upper pumping elements (1) are driven by the rocker arms through camshaft motion (9) to create high-pressure oil inside the oil chamber (2). As the camshaft continues to rotate and the camshaft lobe ramps down, a spring in the upper pumping element returns the piston and the rocker arm to their home positions.

The high-pressure oil in the oil chamber passageway is delivered to the solenoid valve (8) from the upper pumping element. The solenoid valve (8) is a normally open hydraulic control valve. Therefore, the high-pressure oil is vented from the oil chamber to the accumulator (7) unless the solenoid valve is powered. When the solenoid valve is supplied 12 volts, the valve closes and high pressure oil instead acts upon the hydraulic brake pumping elements (6) to operate the intake valves (5).

The hydraulic brake pumping element (6) is essentially a piston that is operated by the high-pressure oil to open the intake valves (5). It also functions as a brake to stop the movement of the pumping element and intake valves. The braking function is the result of vent holes around the perimeter of the element’s cylinder. When the piston approaches full stroke, the lower perimeter vent holes bleed off oil. This stops the piston from moving any farther. When the pressure from the solenoid is taken away, the upper supply holes in the cylinder become bleed holes that allow the piston to return to the home position. The piston is pushed back to the home position by the force of the intake valve springs. As the piston approaches the home position, some of the bleed holes are covered and the speed of the piston is regulated as it approaches the final resting position. This also controls the valve speed as it seats in the cylinder head. The hydraulic brake pumping element also functions as a hydraulic lash adjuster (3) because the valve stem clearance is hydraulically taken up by the piston. This occurs because the hydraulic brake pumping element/hydraulic lash adjuster is always under some oil pressure from the engine oil lubrication system. This creates enough pressure to take up valve clearance.

The variable valve actuator features three areas that function together as an oil reservoir so that the actuator always has a ready supply of engine oil. The engine lubrication system provides oil to the lower reservoir area and keeps it full of oil. To flow from the lower reservoir to the upper reservoir, the oil must pass through very small holes. This helps to purge air from the lower reservoir and to maintain engine oil pressure in the lower reservoir. The third reservoir area, the oil accumulator (7), is filled by oil vented from the oil chamber by the solenoid valve (8). The oil accumulator is a spring loaded accumulator that absorbs the hydraulic shock that would otherwise be created when the solenoid valves are opened. This helps to increase the durability of the system, maintains higher pressure in the lower pressure side of the system and lowers the overall load on the engine oil pump.
 
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The special tools are available from Mopar Essential Tools.
10259A/B MultiAir® Spring Compressor

2025300090 Alignment Pins, Multiair to Cylinder Head

Tighten the ten VVAA retaining bolts in three steps following the sequence shown:
•Step 1: All to 10 N·m (89 in. lbs.).
•Step 2: All to 22 N·m (16 ft. lbs.).
•Step 3: All again to 22 N·m (16 ft. lbs.).

NOTE:
The VVAA and oil temperature sensor wire harness connectors are similar. Verify that the oil temperature sensor wire harness connector is not inadvertently connected to a VVAA solenoid.
 

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If the VVAA is being replaced (new part), it is recommended that the VVAA be primed with NEW/CLEAN oil after installation. This will limit the amount of time it takes for the assembly to fill while cranking the engine. If the cylinder head cover is installed the service port can be accessed through the opening at the rear of the cover (1).
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Using an oil can with a CLEAN soft tip or similar tool like a NEW plastic syringe, force CLEAN, UNUSED oil into the service port (1). Continue to inject oil until oil flows continuously from the bleed port (2) or until a maximum of 200 mL has been injected.
Font Engineering Auto part Machine Automotive wheel system
 
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