Cam Phaser Lockout: Does It Work?
The purpose of the cam phaser lockout is to get rid of the engine clicking noise due to a bad cam phaser. However, locking out the cam phaser can hurt engine performance and fuel economy. This blog will show you how a cam phaser lockout kit actually works, the pros and cons of a cam phaser lockout kit, and its effect on the engine.
What Is Cam Phaser Lockout?
Cam phaser lockout is a chunk of aluminum designed to fit in one of the spaces between vans inside a cam phaser. In this way, cam phaser lockout limits the movement of vanes of a cam phaser so that a cam phaser rattle can be prevented.
Due to this, a cam phaser lockout allows you to keep the cam phasers stationary, eliminating the default variable valve timing (VVT) operation.
In simple words, cam phaser lockouts are just a band-aid for the worn-out problems in the cam phaser that arise due to low oil pressure, bad timing chain, blown tensioner seal, or a bad VCT solenoid.
Before proceeding further, you should first learn the working of a cam phaser, how a cam phaser is controlled, what is VCT solenoid and how a cam phaser goes bad. For this, you can check my detailed guide on the cam phaser.
The Cam phaser lockout kit also comes with a tuner that will allow you to fine-tune or reprogram the engine control module based on your cam phaser settings and allow you to use cam phaser lockouts to improve your engine performance. When there is a problem in the cam phaser i.e. when valve timing is too advanced or too retarded, it can throw a trouble code and turn on the check engine light.
So, once you insert the cam phaser lockout kit, the primary purpose of that engine chips tuner will be to eliminate the check engine light (CEL) you’ll get from the valve timing either being too advanced or too retarded. SCT will reprogram the engine control module and prevent it from adjusting the cam phasing.
The custom tuning of ECM through SCT scanner only defeats the operation of the VCT solenoid valve and blocks the trouble code that would otherwise be thrown due to the cam not retarding or advancing properly. Summing it up, tuning an ECU (Engine Control Unit) ensures that it can’t mess with the cam timing anymore.
What Is The Purpose Of A Cam Phaser Lockout Kit?
The purpose of a cam phaser lockout kit is to eliminate the clacking of the cam phaser by limiting its movement and setting the cam phaser in a full-advanced position.
A small aluminum block is inserted in the cam phaser vanes. By inserting the aluminum block between the vanes of a cam phaser, they will no longer be moved anywhere due to the oil pressure.
In this way, locking out the cam phaser will prevent cam phaser rattling as the vanes of the cam phaser will not clack due to oil pressure problems or timing chain problems in the engine.
The cam phaser lockouts will lock the internals of the cam phaser and will transform a cam phaser into a fixed timing gear without any moving parts and internal mechanisms to make noise or fail.
In the below picture, you can see how a piece fits between the vanes of a cam phaser for the lockout.
While inserting a lockout piece in a cam phaser, don’t forget to change the bolts of a cam phaser cover. Cam phaser lockout kit comes with torque to yield bolts that can be tightened using a torque wrench to yield a snug fit.
A cam phaser is used to modify the timing of the valves in relation to the crankshaft. The cam phaser works by changing the phase relationship between the camshaft and the crankshaft.
By changing the phase angle, the camshaft is rotated ahead or behind the crankshaft to increase or decrease the amount of time it takes for the valve to close, thus increasing or decreasing the amount of intake and exhaust gasses leaving the combustion chamber.
Advantages of a Cam Phaser Lockout Kit
Using a cam phaser lockout kit is an affordable option for a quick fix of a cam phaser rattle issue. Here are the following advantages, a cam phaser lockout kit offers to your engine:
Low-Cost Maintenance
Cam phaser lockout is an affordable fix to eliminate the cam phaser rattle. It is the most common reason for cam phaser problems, which is caused by the lack of oil inside the lifter cam phaser. The phaser is designed to increase the valve lift of the engine, but if there is no oil inside the lifter cam phaser, it cannot work properly.
The cam phaser kit (VCT solenoid, tensioners, timing chain, cam phaser) costs over $2000 to eliminate the cam phaser rattle issue. On the other hand, locking out the cam phaser with less than a $100 cam phaser lockout kit in a full-advanced position will help run your engine quieter and smoother.
Better Fuel Economy (MPG) On Low RPM
A lockout kit eliminates variable valve timing to maximize the engine performance and increase MPG at lower RPM.
Since the cam phaser is fixed in a full-advanced position using a lockout kit, the inlet valve is open and closed before the piston reaches the top dead center and bottom dead center respectively.
This is because, at low RPM (low engine speed), the air velocity entering the engine cylinder through the intake manifold is quite low, due to which the intake valve gets slammed shut before the piston travels back to the top dead center to compress the air.
Eliminates Cam Phaser Rattle
This is a known issue in Ford 5.4 L engine in which the cam phaser rattles due to low oil pressure, and a knocking sound is produced. Cam phaser lockout kit works effectively to eliminate the knocking problem.
For this, the cam phaser lockout kit comes with all necessary parts and it has no cost and no installation is required to use. It is an easy way to eliminate the cam phaser rattling problem.
Disadvantages of Cam Phaser Lockout
The disadvantage of a cam phaser lockout is that it is not a long-term fix for an engine. If your engine is quite old, and you do not take too much work out of it, you can apply a low-cost fix of a cam phaser lockout.
But if your engine has covered only a few thousand miles and it has bad cam phaser problems, you should consider installing a new cam phaser, timing belt, and tensioner seal.
The con of a cam phaser lockout fix is that it only eliminates the clacking of cam phasers. Your engine may still face low oil pressure issues in the cam phaser due to a blown tensioner seal, or a bad VCT solenoid. Also, the timing chain connected to the cam phaser and the chain guide can still go bad.
Another con of cam phaser lockout is the high cost of the engine tuner that comes with cam phaser lockout kits on your request.Â
The tuner costs around $600. It is specifically programmed to maximize the engine performance as it loses a little bit of power with the lockout.
Lastly, cam phaser lockout is not suitable when driving the engine at high RPMS. The Cam phaser lockout kit affects the top-end power of an engine as the engine computer will not be able to retard the cam phaser position, which is necessary to achieve more high-RPM power.
Moreover, your engine may lose more power if the ECU is not tuned after the cam phaser lockout as it will try to control the variable valve timing if it is not tuned after the lockout.
Does Cam Phaser Lockout Affect Engine Emissions?
A cam phaser lockout kit won’t affect emissions if you tune the ECU to optimize the valve timing for no longer having the variable valve timing after the lockout of the cam phaser. So, cam phaser lockout will only eliminate the variable valve timing mechanism in an engine.
Can you not lock the phaser in the center so it’s as if no variable timing is in effect like a non vvt engine with no advance or retard in timing?
Thank you for the thoughtful question. Locking the cam phaser in the center position is theoretically possible, but not recommended in practice. Here’s why:
Most cam phaser lockout kits are designed to lock the phaser in a fully advanced position to help low RPM performance and efficiency. Centering the phaser would lose these benefits.
Even if you center the phaser, the engine computer is still expecting variable cam timing control. Without a tune, it will get confused by the lack of timing change and may set codes or fluctuate.
Locking in the center position can actually worsen cam phaser knocking in some cases. Fully advancing helps stabilize the phaser.
Non-VVT engines are designed and tuned from the factory for fixed cam timing. Simply locking a phaser does not replicate this – the compression ratios, cam profile etc still differ.
So in summary, while an interesting idea, centering the cam phaser with a lockout kit is not an effective solution. Fully advancing with a tune, or repairing the cam phaser system remain the best options.