The rocker arm solenoid valve controls the 2-step lift by controlling the oil flow to the rocker arm. In default mode, a locking pin locks the inner and outer mechanisms of the rocker arm together to provide high lift. When low lift is commanded, oil pressure retracts a locking pin within the rocker arm.
How does a rocker arm solenoid valve work?
When low lift is commanded, oil pressure retracts a locking pin within the rocker arm. The rocker arm solenoid valve receives a signal from the ECM. The ECM controls the rocker arm solenoid valve by supplying a 12 V PWM signal.
What is the function of the rocker arm?
The gas regulation means that the rocker arm functions to keep the internal combustion engine levels at the right pressures, preventing premature combustion. Some engines use shorter rocker arms for their internal process, where the cam lobe pushes down on the rocker arm to open the valve. On this type of arm, the pivot point is at the end ...
What is an endend pivot rocker arm?
End pivot rocker arms are probably self-explanatory. The end of each rocker arm has a pivot point on it. The camshaft is located in the middle of the rocker arm to push down on the end pivot area.
What is a short rocker arm on a cam?
Some overhead cam engines employ short rocker arms in which the cam lobe pushes down (rather than up) on the rocker arm to open the valve. On this type of rocker arm, the fulcrum is at the end rather than the middle, while the cam acts on the middle of the arm.
What is a rocker arm actuator control circuit?
OBD-II Code Decreased engine performance is defined as a "A" Rocker Arm Actuator Control Circuit/Open. The Rocker Arm Control Solenoid supplies hydraulic pressure to the Variable Timing mechanism. This allows the Variable Timing System to adjust valve timing as needed.
What is a rocker arm actuator system performance Stuck Off Bank 1?
The ECM detects a problem in the rocker arm system for bank 1. The oil passages are clogged or the oil pressure is not up to specifications. The rocker arm actuator is clogged with sludge or is sticking intermittently. The engine may have excessive sludge binding the rockers from moving or the oil is too thick.
What does a rocker arm actuator look like?
0:112:023 Signs of a bad Rocker Arm Actuator failing symptoms P2646 Stuck On ...YouTubeStart of suggested clipEnd of suggested clipThe function of the rocker arm actuator is to control the flow of engine oil to the top end of theMoreThe function of the rocker arm actuator is to control the flow of engine oil to the top end of the engine. And provide lubrication to the rocker arm.
What does code P16D0 mean?
a P16D0 code is an oil leak DTC. Advice is to inspect oil galley plugs in cylinder head. P0010 and P0011 are the codes in relationship to the VVT solenoids. Its recomended to change these solenoids in pairs AND change the oil once both have been replaced.
What causes rocker arm failure?
One of the major causes of component failure is faulty manufacturing. This includes all effects that increase brittleness or those inducing cracks and or stress raisers in the component. Improper heat treatment has been considered as major causes of many failures in the literature.
How much does it cost to fix a rocker arm actuator?
Because rocker arm repair is tedious work, it can be time intensive so hiring an auto mechanic or dealership to do the job is not cheap. Expect to pay anywhere from $500 to $1,500 (parts + labor) depending on the vehicle. A good chunk of the expense is for labor as it can take a long time to access the necessary parts.
How do I fix error code P2647?
What repairs can fix the P2647 code?Adding or changing the engine oil.Replacing the timing belt or chain as well as other timing components.Replacing the oil control valve or other variable valve timing components.Repairing or replacing wiring or connectors that are associated with the variable valve timing system.More items...
How do I fix error code P2649?
What repairs can fix the P2649 code?Replacing the 'A' rocker arm actuator.Repairing the wiring harness or connector to the actuator.Following the manufacture pinpoint test to isolate faults in the system.
What is VTEC oil pressure switch?
The variable valve timing oil pressure switch is a normally open switch located at the VVT solenoid. When the VTEC oil pressure switch closes, the voltage should drop to zero. This is how the PCM knows if oil pressure was applied to the VTEC system. When this system fails to operate properly the ECM may set a code.
What is code p16 d0?
The Chevy Malibu fault code p16d0 is usually displayed when - intake rocker arm valve 2 stuck off. This will trigger a check engine light on Your dashboard, just like other fault codes. This fault code is related to an oil leak. To find the problem, You can check the oil galley plugs found in the cylinder head.
What is code P16CF?
Code : P16CF. Make : CHEVROLET. Description : P16CF CHEVROLET Intake Rocker Arm Solenoid Valve 2 Control Circuit. Possible causes : – Faulty Intake Rocker Arm Solenoid Valve 2.
Where is the EGR valve on a 2011 Chevy Malibu?
The EGR valve is located in the engine compartment (underneath the hood).
What is a rocker arm?
Rocker arm. A rocker arm (in the context of an internal combustion engine of automotive , marine, motorcycle and reciprocating aviation types) is an oscillating lever that conveys radial movement from the cam lobe into linear movement at the poppet valve to open it.
Why are rocker arms used in pushrods?
Because the rocker arms are, in part, reciprocating weight, excessive mass especially at the lever ends limits the engine's ability to reach high operating speeds. For this reason, aluminum is often used for high performance, aftermarket rocker arms for pushrod engines as well as many OEM rocker arms on OHC engines.
How does a cam drive work?
The drive cam is driven by the camshaft. This pushes the rocker arm up and down about the trunnion pin or rocker shaft. Friction may be reduced at the point of contact with the valve stem by a roller tip. A similar arrangement transfers the motion via another roller tip to a second rocker arm. This rotates about the rocker shaft, and transfers ...
Where do roller rockers work?
For pushrod engines, roller rockers employ a roller where the rocker contacts the valve stem. Roller rockers can also be used in overhead cam engines. However, these generally have the roller at the point where the cam lobe contacts the rocker, rather than at the point where the rocker contacts the valve stem.
When were rocker arms made?
Dating back to the 19th century, rocker arms have been made with and without roller tips that press upon the valve.
How does a camshaft work?
When the camshaft lobe raises the outside of the arm, the inside presses down on the valve stem, opening the valve. When the outside of the arm is permitted to return due to the camshafts rotation, the inside rises, allowing the valve spring to close the valve. Some overhead cam engines employ short rocker arms in which the cam lobe pushes down ...
How does a rocker arm work?
Rocker arms have “ratios” -- the ratio is a measure of the arm’s leverage, which in turn determines how powerful the force is that it can transfer to the valve stem. The ratio is determined by the length of the arm, both between its center of rotation and the point it contacts the cam lobe, and between its center of rotation and the top of the valve stem. A typical automotive rocker arm has a 1:1.5 ratio, meaning that it moves the valve one and a half times further than the peak of the cam lobe projects up from the camshaft.
What is the rocker arm?
The rocker arm of an internal combustion engine changes radial movement into linear movement; this kind of device is properly called a reciprocating lever. It takes the spinning motion of the overhead camshaft and turns it into the up-and-down movement that opens and closes the valves. Because they are typically made of steel, rocker arms have a great deal of strength for their weight, and can therefore exert a great deal of leverage.
How does a valve work when the lobe rotates away from the rocker arm?
As the lobe rotates away from the rocker arm the outside drops, the inner end lifts and the valve’s spring closes it. In this way, the opening and closing of the valve is kept in sync with the rotation of the cam shaft, and thus with the movement of the pistons.
What is the cam end of a rocker?
Valve. Just as the outside end -- the “cam end” -- of the rocker arm moves up and down, so does its opposite side. As the cam lobe comes round it lifts the outside of the rocker arm, which rocks, and the inner end pushes down on the valve stem, opening it against its spring.
How does a cam move?
The cam’s movement is transferred to the rocker arm by a device called a cam follower, of which there are different types that vary by manufacturer and by vehicle age. As the cam shaft spins, the part of the rocker arm acted upon by the cam follower is lifted and lowered, lifted and lowered.
Is a camshaft a spherical rod?
The camshaft is not a true spherical rod; it has bulges on it called lobes. The lobes project outward from one side of the shaft, while the back of the shaft -- opposite the lobe -- does not have a projection. As the shaft rotates, the side with the lobe lifts the outside end of the rocker arm, and then the side without ...
Why are rocker arms bad?
1) Weak Engine Performance. Since the drivetrain and rocker arms help the engine generate power and transfer it to the driving wheels, there will be a problem in this process if the rocker arms are damaged or not working properly. It won’t take long for you to experience a weak engine performance as a result of bad rocker arms.
What is the difference between rocker arms and camshafts?
There are numerous types of rocker arms manufactured for vehicles. The differences between them relate to their levels of durability and friction. The most crucial difference is how they move the camshaft.
What is a stamped steel rocker?
Stamped steel rocker arms are used more than any other type of rocker arms. Auto manufacturers love stamped steel rocker arms because they are fast and affordable to manufacture.As the name indicates, these rocker arms are stamped from a single metal piece. It uses a nut with a round bottom to secure the rocker in place with a trunnion pivot. The rocker can pivot up and down while the rocker stays secure.
What is the purpose of the pushrods on a camshaft?
The pushrods assist the rocker arms in making sure they ’re able to open and close these valves completely. The pushrods are associated with the camshaft. If the pushrods push up, the rocker arms push ...
How many types of rocker arms are there?
Below are the five types of rocker arms.
How much does it cost to replace a rocker arm?
The cost to replace one rocker arm is generally between $500 and $1,000. In most situations, you’ll probably have to replace multiple rocker arms too because they tend to wear out or go bad inside your vehicle at the same time.
Where is the camshaft on a rocker arm?
End pivot rocker arms are probably self-explanatory. The end of each rocker arm has a pivot point on it. The camshaft is located in the middle of the rocker arm to push down on the end pivot area.
What does a rocker arm do?
The rocker arm controls the amount of time each intake and exhaust valve is open, so it makes sense that if one of them isn’t functioning correctly, you’ll notice some performance issues. While weaker than normal engine performance is typical, a stalling engine is not.
How does a rocker work?
In purely mechanical turns, the rocker arms transfer the vertical reciprocal motion from the pushrods to the exhaust/intake valves. It might not sound like much, but without these little contraptions in your engine, you wouldn’t start, and you wouldn’t get any air into or out of the combustion chamber.
What does it mean when your rocker arm is bad?
The most common symptom of a bad rocker arm is clicking or ticking noises coming from the cylinder head of the engine. It can also cause misfires or a stalling engine together with a check engine light on your dashboard.
Why does my engine make a clicking noise?
Once you’ve ruled out any external causes, you can start worrying about internal issues like a broken rocker arm .
How to tell if a rocker arm is broken?
Once you suspect a broken or worn rocker arm, the only way to 100 percent verify that the rocker arm is the issue is to remove the valve covers and see what’s going on underneath. If your vehicle has worn rocker arms, you’ll notice excessive play or metal underneath the rocker arm. If the rocker arm is extremely damaged, you might even find a cracked rocker arm.
How much does it cost to replace a rocker arm?
Rocker Arm Replacement Cost. The average single rocker arm replacement cost ranges from $500 to $1,500 – and almost all of this cost is for labor. In fact, each rocker arm typically costs between $5 and $20. But that’s not the only parts you’ll need.
Where are the rocker arms located?
The rocker arms are located at the engine head, connecting the camshaft to the exhaust and intake valves. When you look at your engine, you’re not going to see the rocker arms. That’s because they’re underneath the valve covers that are positioned directly over the engine’s heads.
What is the code for a rocker arm oil pressure switch?
If the PCM does not receive the correct voltage signal back from the rocker arm oil pressure switch, it may set code P2646.
What is the DTC code for a rocker arm actuator?
Diagnostic Trouble Code (DTC) P2646 code stands for “A” Rocker Arm Actuator System Performance/ Stuck Off (Bank 1).” It’s a generic OBD-II powertrain code supported by a variety of makes and models.
What is a VTEC solenoid?
In vehicles equipped with VTEC, the rocker arm control solenoid supplies hydraulic pressure to the variable timing and lift mechanism. This allows the VTEC system to adjust valve timing and lift as needed. The VTEC system controls the rocker arm control solenoid through the powertrain control module (PCM).
Does a GM Ecotec have a locking pin?
GM Ecotec engines have a similar three-lobe setup, but the locking pin moves perpendicular to the camshaft rather than parallel to it, and Ecotec engines can store the same code for the same reason – it’s all about whether the oil pressure is being delivered to move the locking pin.
What is a rocker arm?
A rocker arm is essentially a small lever in your engine that turns radial movement into linear movement. In other words, it turns the spinning movement from the camshaft into an up and down movement that opens and closes the valves. That’s a pretty important job, as stuck valves can cause many serious engine issues.
Why are rocker arms so strong?
That said, rocker arms can become damaged or loose. Your engine won’t run correctly if the rocker arms are damaged because the valves will no longer open and close correctly.
What does it mean when your rocker arms are ticking?
Ticking or tapping noises are perhaps the most common and easily identifiable symptom of bad rocker arms. The sound will be at its loudest when starting the engine or idling.
How much does a rocker arm cost?
A single rocker arm will cost you anywhere from $15 to $60.
How much does it cost to replace a rocker arm?
For a garage to replace your rocker arms, you can expect to pay anywhere in the region of $500 to $1,500. That price is inclusive of parts and labor.
Can you see rocker arms damage?
Visible Rocker Arm Damage. And last but not least is visible damage to the rocker arms. Unfortunately, in order to see the visible damage, you’ll have to take off the valve cover and inspect the state of the rocker arms. This will usually require a mechanic as you’re pretty much taking the engine apart at this point.
Do you need to replace rocker arms on a car?
You will need to replace your engine’s rocker arms if they’re damaged, as the symptoms only get worse if you continue to drive.
