How to Lower the Exhaust Temperature in a Diesel Motor

by Natalie Lyda

Exhaust gas temperature, also referred to as EGT, measures the temperature of gasses leaving a diesel vehicle's exhaust manifold. Excessive exhaust temperatures are a primary culprit of diesel motor failure, as high temperatures can cause metal components to weld together or suffer catastrophic failure. A gauge known as a pyrometer is the best way to monitor exhaust gas temperatures, and allow drivers to understand the amount of heat being created within a diesel motor's cylinders. Installing aftermarket parts to help regulate exhaust gas temperatures will extend the life of the motor and assist with increased performance.

Provide additional airflow to the motor by installing an aftermarket, cool air intake in place of the stock air filter. High exhaust gas temperatures are caused by too much fuel and too little air within the diesel motor's cylinders. Facilitate the efficient consumption of fuel, and lowered exhaust temperatures, by allowing more clean air to flow into the motor and reset the appropriate air to fuel ratios.

Install a free-flowing, large diameter exhaust system. Allow exhaust to exit the vehicle with as few restrictions as possible, which will provide a platform for the turbocharger and motor to produce additional power without a significant increase in exhaust gas temperature.

Supply the diesel motor combustion chambers with an additional catalyst to consume fuel by installing a water and methanol injection kit. While the methanol helps to burn any excess fuel in the cylinders, the spray of water provided by a water/methanol injection kit will help cool down the hot air exiting the vehicle's turbo. Water/methanol kits are capable of supplying additional horsepower while also reducing exhaust gas temperatures by an estimated 200 degrees.

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