Reviewed by Shannon Martin, Licensed Insurance Agent.
If you want to warm up your diesel vehicle before hitting the road, knock yourself out—but idling for more than a minute or two is unnecessary, even for a diesel engine.
Diesel engines are now computer-controlled and designed to warm up quickly, thus reducing the amount of time you need to idle to reach the ideal operating temperature. If you let a newer diesel engine idle for too long, it can cause problems including:
Intake manifolds (which evenly distribute the air and fuel mixture to the engine’s cylinders) can gather more soot than is recommended
DPF (diesel particulate filter) can clog up faster, causing burns and wasting fuel unnecessarily
The best thing you can do to warm up your diesel engine—after letting it idle for no longer than two minutes—is to start driving it. Heading off at a steady pace will heat up the engine and get the oil circulating. But don’t hit the gas too hard, as slamming a cold engine with high RPMs can lead to excessive wear and tear.
Your diesel engine might be able to warm up easily, but your vehicle can’t protect itself—it needs a robust
Jerry partners with more than 50 insurance companies, but our content is independently researched, written, and fact-checked by our team of editors and agents. We aren’t paid for reviews or other content.