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VVT Engine Problems and How to Fix Them

If your car is experiencing problems with the Variable valve timing system (VVT-i), you are not alone. This article will go over the VVT-i engine’s components, the common symptoms and maintenance. Once you have understood what’s wrong with the VVT-i, you’ll be better equipped to diagnose the problem yourself. After all, it’s your car! What’s the worst thing that can happen to your VVT-i?

Variable valve timing system

Several factors can lead to a failing VVT system. These include a massive decrease in fuel efficiency, a drop in power, and a noticeable decrease in performance when under load. Incorrect timing can also result in increased exhaust emission and smoke. These problems should be addressed immediately to avoid further damage to the engine. The following are some common causes of VVT system problems and how you can fix them.

A failing VVT solenoid is one of the most common causes of an emitted check engine light. While this is a warning, the actual problem may be caused by a faulty VVT solenoid or another problem. In such cases, it is best to visit an ASE-certified mechanic for diagnosis. Listed below are some symptoms of a failing VVT solenoid.

The first step is to disconnect the battery. The battery can be disconnected by twisting the terminals and pulling them out of place. You will need a bungee cord to secure the cables, which should be separated from each other. Once you have disconnected the battery, you can move onto the next step, replacing the VVT solenoid. Be careful not to damage the engine while replacing the solenoid.

A failed variable valve timing solenoid can also be the cause of an engine misfire or stumble. While the solenoid is not always the problem, it can affect the flow of oil to the other components of the engine. Moreover, dirty oil can block the passage between the VVT solenoid and the rest of the system. Consequently, the engine’s performance will be decreased.

In addition to the valves, there are also the camshafts. These valves open and close hundreds of thousands of times each. Early engine technology only opened or closed the valves for a specific amount of time. Today, advanced technology allows engine manufacturers to vary the valve timing between each stage, thus boosting fuel economy, generating more power, and limiting emissions. The downside of the VVT is a loud ticking noise, which can be heard during acceleration or braking.

Components involved

When you notice that your vehicle’s ignition is misfiring or stumbling, it may be time to bring it to a mechanic. Most (VVT) systems rely on the proper circulation of the engine oil to function properly. When the oil flow is faulty, however, the system can become damaged and eventually fail entirely. The first step is to diagnose the problem to determine if it is caused by one of the components.

A malfunctioning VVT system causes massive loss in fuel efficiency, engine power, and performance under load. The engine’s valve timing may also be off, resulting in incorrect combustion, increased exhaust emissions, and higher exhaust smoke. Ultimately, you need to contact a mechanic to have your car fixed or repaired. Fortunately, most cars these days come with a service manual that will give you a step-by-step guide to troubleshooting the problem.

Traditional engines use a fixed valve timing system. Modern VVT systems allow for camshaft position adjustment to alter valve timing. By changing the timing of each individual valve, you can increase fuel efficiency and improve engine performance. A hydraulic actuator is located at the end of the camshaft. It varies the camshaft’s position by retarding or advancing the valves. The VVT solenoid activates the actuator through oil pressure. The PCM controls the valve timing solenoids based on inputs from different sensors, including temperature, fuel type, and engine speed.


If your car is exhibiting the symptoms of a VVT engine problem, you may need to contact an expert mechanic. While you can do some diagnostic tests yourself, a certified mechanic can help you determine the root cause of the problem. In many cases, the switch itself is not the culprit. In these instances, an ASE certified mechanic can properly diagnose the problem without replacing the switch. A proper diagnosis can also rule out other potential issues.

The Check Engine Light will illuminate if your vehicle’s ECU detects a problem with the VVT solenoid. The VVT switch is an electrical component that the car’s onboard computer constantly monitors. When the switch fails, or the data it receives is inaccurate, the computer will alert the driver. The Check Engine Light will be illuminated, so contact your mechanic immediately. If you have noticed any of these symptoms, your vehicle may be experiencing one or several of the following problems.

Bad VVT solenoid: Another common issue with the VVT system is the faulty timing. A bad VVT timing can cause additional oil to flow into the engine during idling, causing the car to over-rev. If this happens, the engine might also stall or exhibit rough handling. A faulty VVT solenoid can result in expensive repairs. If you suspect that the solenoid is the culprit, you should contact a reputable mechanic for diagnostic and repair services.

Another common issue with VVT is a dirty engine oil. If this is the case, then the VVT solenoid is out of order. If the valves do not open and close properly, fuel will be wasted and performance will drop. A dirty engine can also cause oil to flow to the VVT solenoid, causing a poor performance. Your car’s Check Engine Light may also turn on to alert you to a potential problem.

If the problem persists, check the VVT solenoid. It is located near the front of the engine in the front part of the valve cover. Pull the biggest part of the solenoid out of the engine compartment. Then, you should replace it with a new one. Be sure to keep the old solenoid in a safe place to prevent the wires from coming in contact with them.


You can fix your VVTI engine problems by contacting an ASE certified mechanic. It is essential to get the engine checked by an expert to avoid additional damage. A certified mechanic has access to factory codes and can determine if your car needs VVT system repair. Here are some common problems with this type of engine. Checking the spark plugs for flooding is an easy way to fix this problem. High fuel consumption is usually connected with a failure of the lambda probe. Replace the lambda probe, air filter and mass air flow sensor, and you can fix valve stem rings and seals.

Incorrect motor oil is one of the main causes of VVT problems. People tend to use the wrong motor oil, which isn’t necessary for a normal engine. In summer, people use heavier motor oil and don’t use synthetic oil to save money. Other problems are specific to VVT engines, but you can find a guide to prevent them by reading this article. VVT is a system that uses variable valve timing to optimize the efficiency of available power. It was discovered back in the 1850s by railroad engineers.

Faulty variable valve timing sensors are another major cause of VVT problems. Faulty VVT sensors can cause the VVT to be too advanced or too retarded, causing a Check Engine Light to illuminate. If you notice that the check engine light is on, it’s time to visit your local mechanic. If it’s not there, you should get your car towed. A mechanic will inspect the engine and recommend any needed repairs.