Your Cummins diesel engines have an air heating grid located on the intake manifold. The heater grid is used to raise the incoming air charge as the air passes over the grid. This heated air charge aids in the ignition of the diesel fuel-air mixture. This heated air charge is used to aid the starting of your Cummins diesel engine when it is done to help the engine start and improve driveability with cool or cold outside temperatures. A warm mixture of fuel and air allows the diesel combustion cycle to start. The heater grid will continue to cycle until the engine has reached its correct operating temperature.
The sole purpose of the heater grid is exactly the same as that of glow plugs. To warm the incoming air charge during cold starts. Diesel engines use glow plugs and heater grids to aid with cold starts.
The location of the intake heater grid varies between the diesel engine series. They are usually located between the intake horn and the intake manifold,
The heater grid is an electrical device that is powered by your batteries and alternator. The heater grid will cycle on when you first turn on your key if the outside ambient temp is cold enough.
How do you verify the proper operation of the Intake Heater Element?
When the temperatures drop and the engine is running and cold, you will see fluctuations in the voltmeter. These fluctuations will appear as an up and down movement on the voltmeter. If your headlights are on you may see a dimming effect on the light output when the heater grid is activated. When the engine reaches a predetermined temperature this cycle will stop and the dashboard light will turn off.
The proper use of a coolant heater will play a big role in the time required to start your engine. When you plug in your truck it heats the engine coolant throughout the engine block. This also raises the temperature of the engine oil which makes it easier to spin over with proper lubrication rates.