Volumetric Efficiency Calculator
Use this tool to determine if a MAF is probably functioning correctly.
Note: This is set up for Naturally Aspirated engines.
Data Used for VE calculation
Mass Airflow (g/s):
Intake Air Temperatue (F):
Engine Displacement (L):
Intake Air Temperatue (K):
Baro (Pa):
Density:
Your Volumetric Efficient(VE %) is :
Before concluding that there is an issue, please review your data and UNITS for accuracy.
If your data is good, this low VE value is telling you that your engine is not breathing effectively.
VE is a percentage and cannot be above 100% for a naturally aspirated engine. If you're working with a N/A engine, your data and/or units must be wrong.
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The following table may help you diagnose your vehicle:
| VE |
Fuel Trims |
MAF Reading |
O2/Air Fuel Reading |
Possible Causes |
Next Step(s) |
| Low |
High |
|
|
Mechanical issue, e.g. valve seating, burnt valves, cam lobes, cam timing, piston rings... |
Run mechanical test issues, e.g. compression, leak down, vacuum guage, ... |
| Low |
High |
Low |
|
MAF could be dirty or broken |
Snap Throttle signal signature test; perhaps cleaning it will resolve issue. |
| Low |
High |
|
Lean |
Fuel Delivery |
Check fuel pressure, check injectors, ... |
| Low |
Good or Slightly Low |
|
|
Excessive exhaust back pressure |
Run exhaust back pressure tests |
Related Videos
OTC Tools - Volumetric Efficiency Testing with the Encore