Volumetric Efficiency Diagnostics
A few years ago, I obtained an OBDII scan tool/dynamometer simulation/calculation program that can graph volumetric efficiency (VE) over rpms. Using real world vehicles, and no useful instructions, I devised a test sequence that allows a technician to see things another way. What is Volumetric Efficiency? Let’s keep this simple to start. An engine is
Oil-Related Engine Codes for VVT Engines
Variable valve timing is becoming a standard system on most late-model engines because it offers higher performance from a smaller displacement engine at higher rpms. Oil plays a larger role in VVT systems. They need engine oil not only for lubrication, but also to actuate the camshafts to change the profile of the lobes. Oil
Harmonic Dampeners: Why They Fail, What to Look For
Every time a cylinder fires, the crankshaft speeds up a very small amount for a short period of time. It is then slowed down as the next cylinder in the firing order compresses air and fuel for the next combustion event. The speeding up and slowing down of the crankshaft produces torsional vibration or twisting
Be Careful When Replacing That Diesel Air Filter
Modern passenger and light-duty diesels with ECMs have mass airflow sensors and precisely control fuel delivery. Key to the efficiency and lifespan of the diesel engine is the diesel air filter. A restricted air filter will not affect fuel economy but will drastically affect power output. We asked prominent filter manufacturers for some diesel air
