Should You Be Driving With VCT Solenoid Unplugged?
The variable camshaft timing solenoid is a component that is responsible for managing fuel economy and engine performance. However, it’s not a mandatory part of driving your car.
So, should you be driving with VCT solenoid unplugged?
No, you should not drive with the VCT solenoid unplugged. The VCT controls the oil flow based on engine speed and load. Without a VCT solenoid in your vehicle, your car will have poor fuel economy and low engine performance. If you drive your car with it unplugged for a long time, it may damage your engine.
In the following sections, we will shed light on what happens when you drive without a VCT solenoid. Also, we will cover how to deal with a faulty VCT solenoid.
Contents
Can You Drive With the VCT Solenoid Unplugged?

Yes, it is possible to drive with the VCT solenoids unplugged. The VCT solenoids adjust the timing of opening and closing the intake valves depending on the engine load and RPM. So, without the VCT solenoids, you should be able to drive your car.
But with the VCT solenoids unplugged, your PCM will disable the variable camshaft timing system. Then the air and fuel intake and exhaust will not be optimized anymore.
As a result, engine performance will decrease and fuel consumption will increase. You might feel your vehicle is losing power when accelerating. So, to summarize, it is not optimal since it decreases fuel efficiency and engine performance.
What Happens When You Drive With the VCT Solenoid Unplugged?
The VCT (variable camshaft timing) solenoids are controlled by the PCM and are responsible for air and fuel flow to the engine camshaft.
With oil pressure, VCT solenoids control intake and exhaust valve timing based on engine RPM and load. The solenoids use oil pressure to move the cam phasers, which are then held by their locking pins. This manipulates the timing of the opening and closing of the intake and exhaust valves.
This solenoid optimizes the performance and fuel consumption of the engine as needed, depending on the RPM and load. Your car will have different RPMs for different speeds; that means the RPM depends on the speed of the car.
When you unplug the VCT solenoids, the camshaft will open and close the intake and exhaust valves by default, instead of what the engine requires.
As the opening and closing of the intake and exhaust valves are not optimized, this reduces the engine’s performance and fuel efficiency. Also, the PCM would detect an open circuit and disable the variable valve timing system. This would result in the PCM limiting certain operations and displaying a constant error code.
Removing the VCT solenoid would also affect the exhaust valve. As a result, your engine will emit more harmful chemicals into the atmosphere.
Now, here is where it gets interesting, if the cam phasers cannot be moved by oil pressure, it does not matter whether you have VCT solenoids plugged in or not. The same thing applies if the cam phaser position cannot be held by its locking pins.
With a fault in the cam phasers or the VCT system, the solenoids make no difference. In both of these scenarios, the engine will not be giving its maximum output and will be prone to wear and tear.
Other than high fuel consumption and low engine performance, driving with VCT solenoids can also have a few long-term effects. For example,
- The timing belt tensioner could break
- The valves could malfunction due to less lubrication
- The camshaft phaser could stop working
When these problems arise, your engine will also fail, meaning it won’t be possible for you to drive your car.
How Much Time and Distance Can You Drive with the VCT Solenoid Unplugged?

You will have to drive an engine with high fuel consumption and low output if you unplug the VCT solenoids. This will not really affect your engine in the immediate future, but it will cost you money if you do it for a prolonged period.
The amount of time and distance you can drive with your VCT solenoids unplugged depends on how much stress you put on your engine. The VCT solenoid can make a great deal of difference if you drive at high speeds or carry a heavy load regularly.
If that’s the case, your engine will be put under a lot of stress, leaving it vulnerable to damage. It doesn’t matter why you are driving with the VCT solenoids unplugged; it would be best to fix the problem and plug them back in ASAP. If not, your vehicle will face many problems, such as ford starting and then dying immediately.
But if you do not have to drive around at high speed or carry heavy loads, you can drive with the VCT solenoids for quite a few weeks. But your engine will consume more fuel and produce less power in comparison.
When Do You Drive with the VCT Solenoid Unplugged?
When there is a malfunction in the VCT system or the solenoid, driving your car can be problematic. In that case, removing the VCT solenoid would deactivate the VCT system, temporarily solving the issue.
The VCT solenoid or the whole VCT system is there to optimize the air-fuel flow to your engine to improve fuel consumption and engine performance. The VCT system is not mandatory for driving, but it definitely helps.
However, on some occasions, the VCT solenoids or a component of the VCT system can malfunction. A malfunctioned VCT system can cause loud engine noises when driving, such as engine stalling, rough idling, engine misfiring, etc.
In such cases, it’s better to unplug the VCT solenoids to disable the VCT system for a better driving experience. But a proper diagnosis of the VCT system is required, as these are common engine problems caused by many other problems.
Also, keep in mind that it’s not okay to keep driving with the solenoids detached. Quickly solving the issue and reactivating the VCT system by plugging in the solenoid would be best for your vehicle.
Symptoms of a Failing VCT System:
The symptoms of a bad VCT solenoid or failing VCT system are:
- The check engine light will come on.
- The engine will make loud noises when accelerating
- Engine stalling
- Rough idling
Diagnosis:
Quite a few components make up the VCT system, so diagnosing them all is important to pinpoint the problem. Here are the best possible ways to diagnose any issues with the VCT system-
- Check the VCT solenoid first. Inspect it for visual damage.
- If it looks fine, then check if it works. For that, connect it to your car battery. If the solenoid works fine, you should hear a click.
- Check all the wiring and connections going in and out from the VCT solenoid, especially to the ECU.
- Next up, check the camshaft phaser. Check for damage, corrosion, or debris.
- Then you should check the VCT phaser indicator fingers on the left and right heads. There should be five indicator fingers on the phaser. An “L” should be above the odd finger on the phaser sprocket in its normal state.
Solution:
If the solenoid is damaged or doesn’t work, you will have to replace it. If that’s the case, you’ll need to replace the wiring or connectors as well.
A corroded camshaft phaser can be cleaned. But a damaged one needs to be replaced.
If the phaser indicator’s odd finger is on the right side, that means it was installed incorrectly. If it’s on the left, then that means debris is stuck inside of it, causing an under rotation. In this case, disassemble your cam phaser to determine the problem.
If you cannot determine the problem or the whole procedure is beyond your skill level, then it’s best to call a mechanic.
Frequently Asked Questions (FAQs):
What happens when the VCT solenoid is bad?
When the VVT solenoid malfunctions, the valve timing cannot advance or retard in the correct manner. Thus, the engine may exhibit performance problems, such as rough running and poor acceleration.
Is a VCT solenoid important?
Yes, the VCT solenoid is very important. Although it is not a mandatory part of starting or driving the vehicle; it plays an important role in optimizing engine performance and improving fuel efficiency.
Are a VCT and a VVT solenoid the same?
No, a VCT and a VVT solenoid are not the same things. VCT systems typically use a single solenoid to control the timing of both the intake and exhaust valves, while VVT systems may use multiple solenoids to control the timing of individual valves or groups of valves.
Conclusion
Driving with the VCT solenoid unplugged is not recommended, as it can have negative impacts on the performance and fuel efficiency of your vehicle.
However, if the VCT solenoid or the VCT system is failing, it could cause several problems while driving. Therefore, it would be a temporary solution to disable the VCT system by unplugging the VCT solenoid.
But in those cases, resolving the problem ASAP and plugging in the VCT solenoid would be the best course of action.