In recent years, to keep up with ever growing strict emissions and fuel economy requirements, automakers have turned to the “big-three’’ engine technologies: turbocharging, direct fuel injection and variable valve timing or VVT for short.
The VVT’s name may be longer that the component its self, but its job is crucial for the smooth operation of your turbocharged engine.
Now, you are probably wondering what exactly the VVT does, just hang tight for a second and I’ll give a real-life example.
The basic idea is that the VVT opens and closes to allow more less fuel and oxygen enter the cylinder according to the conditions.
Here’s that example I promised. Imagine for a second that your cruising down the highway, a large semi pulls up along side you. As you press down on the accelerator, the VVT in your engine increases the flow of fuel to the cylinders.
With a fresh burst of speed, you pass the truck.
The VVT allows just the right amount of fuel to enter the cylinder to give just the right amount of speed and torque.
The critical parts to the system are the components responsible for speeding up or slowing down the valve timing to response to driving conditions.
Some systems are slightly different, though they all use motor oil as a hydraulic fluid to move the critical pieces. Many accomplish this with cam phasers that provide extra rotation to the camshaft, thereby adjusting when the valves open and close.
Most of a turbo engine's characteristics come from how far and long it’s intake exhaust valves open, and when they open and close. If you open the valves more, and keep them open longer, you get a powerful, muscle-car idle and high-rpm horsepower.
If you do the opposite, and you get a more civilized engine with a consisting idle, good low-rpm torque, superior fuel economy and lower emissions.
It is the job of the VVT to give just the right amount of balance.
The solenoid directs the oil flow based on info from the computer. As the pressurized oil enters the middle ring. Then it sends oil out the top or bottom ring to speed up or slow down the timing.
In the case of this engine, deposits of impurities prevent the oil from flowing properly. The computer then detects incorrect valve timing and illuminates the check-engine light.
VVT components typically contain tiny openings that the oil flows through to function properly, these openings are .007 of an inch across, which is about the thickness of two sheets of paper.
Even the slightest amount of sludge can lodge in these tiny openings and negatively affect the system. (See picture.)
In some cases, dealerships view these problems as non-serviceable and they recommend a costly engine replacement instead of repairs.
The good news is, many VVT issues can be completely avoided simply with a combination of proper maintenance and high-quality oil and filtration. AMSOIL synthetic motor oil resists deposits and sludge better than conventional oils, helping keep sensitive VVT components clean and functioning properly. It also resists viscosity loss, meaning it consistently performs the duties of a hydraulic fluid, which is vital to proper operation of VVT components.
A large majority of vehicles have VVT engines, so be extra sure to follow appropriate oil change guidelines. Many engines with VVT are also turbocharged, including Ford Eco-Boost and Chevy Turbo Diesel.
Turbocharged engines automatically fall under the severe-service category, meaning customers who use Signature Series Synthetic Motor Oil can extend their drain intervals up to 15,000 miles, 700 hours or one year if they choose.
Even if you are not interested in extended drain intervals, Signature Series is an excellent choice for maximum engine and turbocharger protection. You should also be using AMSOIL Ea® Oil Filters. They offer a filtering efficiency of 98.7 percent at 20 microns. Twenty microns is roughly 10 times smaller than the openings in the solenoids pictured above. Compared to conventional filters, Ea Oil Filters do a better job trapping and holding the deposits that could otherwise end up negatively affecting VVT components.