Active Decompression Technology

Jacobs Active Decompression Technology® (ADT®) allows drivers to experience smoother start-ups with faster starting times and engine shutdown without engine-induced cabin vibration.

down arrow
JVS's Active Decompression Technology® Technology

Performance Benefits of Jacobs ADT

  • Eliminates engine-shutdown-induced cabin vibration
  • Faster transition from eMotor to ICE in hybrid vehicles
  • Improves driver satisfaction
  • Increases engine cranking speed for easier start-up
  • Improves cold start
  • Lowers cranking torque & current draw
  • Reduces starter system wear
  • Reduces crank and bearing starting loads and wear
  • Simple, cost-effective design
  • Compliments start-stop fuel savings strategies
  • Increases driver willingness to use optional start-stop
ADT Performance Summary

How Jacobs’ ADT Works

During Start-up
When the engine is turned on, the ECU automatically activates the device to keep the engine valve open. This keeps the engine in a decompressed state, which decreases the cranking torque and allows the starter to spin the engine at a higher speed.

During Shutdown
Upon shutdown, the ECU activates the device to keep the engine valve open. By keeping the valve open, the engine is able to coast to a smooth shutdown without causing the cab to shake.

Cold Start Up
In cold temperatures when an inlet air heater is used, the engine can be turned over while decompressed. This allows pre-warming the inlet air and engine cylinders without the engine load from compression. This is especially important when battery levels are low due to freezing temperatures. After the warm-up period is completed, the engine compression can be reactivated and fueling can begin.

ADT in Action

Active Decompression Technology is just one of the technologies on Jacobs latest demonstration vehicle which will be touring the U.S. 

Jacobs Demonstration Vehicle

ADT Tech Talk

For a deeper dive into Active Decompression Technology, watch Jacobs' Tech Talk video.

Let's talk about your program

Our engineers are always available to discuss your current or future technology challenges. Contact us using this form, and a member of our team will contact you within two business days.

We collect your name, company, country, and email address so that a Jacobs representative may contact you to answer your questions. Review our privacy notice for additional information on how we protect and manage your submitted data.

Learn more

Download this information package for more details and technical information about Jacobs’ Active Decompression Technology.