Is the VTC control actuator the same as the VVT solenoid?

Thursday January 07 2021
By Paul Kaganzi

My car has an automatic transmission and I need a VCT replacement. Is the variable timing control actuator (VCT) replacement the same thing as variable valve timing solenoid replacement?


Mike, the variable timing control actuator is the same as the variable valve timing solenoid. Different car manufacturers and technicians use either of the expressions to mean the same thing. Variable valve timing (VVT) technology was developed and employed by car manufacturers over the last two decades to achieve the most fuel efficient and peak performance of an engine.

The VVT system uses electronic signals from the engine ignition system, in response to changing engine load or driver demand, to continuously adjust or vary the angle or lift of air intake valves. It is like adjusting your charcoal cooking stove air vent door to vary the intensity of the fire in order to regulate efficiency of heat and charcoal management.

The VVT system relies on the variable valve timing solenoid to actuate the VVT gear system by releasing engine oil. The VVT solenoid or actuator can fail when it gets blocked by counterfeit, wrong grade or aged engine oil with sludge. As a result, the crucial and costly VVT chain and gear system will be damaged by the oil starvation.

In extreme cases, this damage will lead to retarding (wrong setting) of the engine timing which can cause serious valve to piston damage in the long run. In most cases, when you need to replace the VTC actuator or solenoid, consider replacing the timing chains, chain guides and camshaft/crankshaft gear sprockets. Also, manufacturer recommended oil grade and regular periodical oil change is crucial to maintain this system.


My car stalls when warm

My car keeps stalling randomly when it warms up. I have replaced the fuel pump, fuel filter and relay. Could it be a faulty fuel pump?


Hello Tony, whereas a faulty fuel pump or fuel pump relay can cause an engine stall when they warm up, there are other electronic components such as the crank shaft and camshaft position sensors that can cause engine stall when they warm up. These sensors use magnetic hall effect to monitor the movement of the crank shaft and cam shaft. This information is used by the engine management computer to adjust ignition (spark) and fuel supply.

Either of the two sensors can fail when they lose their magnetism. When either of these sensors fail, you will experience engine stalling or failure to start.

A computer diagnosis can confirm if any of these sensors is faulty.

Can I use the battery saver to switch off lights?

I recently bought a 2017 Nissan Frontier without auto headlights. I was wondering if I can leave my headlights on and let the battery saver feature shut them off?


Hello Sky, on your Nissan Frontier, the head lamp battery saver feature is designed to turn off your head lamps after five minutes when you turn off the engine and unintentionally leave the head lights switch in the “on” position. This is designed to save your battery from going flat when the engine is not running. The battery saving feature is not a courtesy delay light feature. The battery saver function takes a long time (five minutes) to switch off the head lights.

It is an emergency battery saving feature for occasions when you forget to switch off the headlights. Nissan recommends that you turn the headlight switch to the “off position” when the engine is not running to avoid discharging the battery. When you use the battery saver function to switch off your head lights after five minutes, you may fail to start the car when your battery is drained.

Even though the battery saver feature automatically turns off the headlights after a period of time, you should turn the headlight switch to the off position when the engine is not running to avoid discharging the vehicle battery.