Heavy-duty trucks use diesel engines for their reliability, performance, and fuel efficiency, along with the relatively low cost of diesel fuel compared to gasoline. While these advantages make diesel an excellent choice for commercial vehicles, this engine style also has its share of problems. In particular, the design of a diesel engine requires correct fuel delivery and timing for efficient operation.
Issues with diesel fuel delivery can affect how your truck operates or even cause significant and severe engine damage. These three symptoms indicate a likely problem with your fuel system, and all of them require immediate attention.
1. Hard Starting
Diesel engines are notorious for hard-starting issues. However, anyone who's driven a newer rig for any significant amount of time knows that these issues generally shouldn't occur on a well-maintained vehicle. Extreme cold weather can sometimes strain even diesel engines in good condition, but warm weather starting issues often point to a problem with fuel delivery.
In most cases, hard starting results from insufficient fuel delivery. Common causes include dirty or failing injectors, a clogged fuel filter, or an issue with the fuel pump. Any of these problems will eventually cause additional drivability concerns, including a loss of power and fuel efficiency. A failing injector can even cause internal engine damage if it's left for long enough.
Unlike gasoline engines, diesel engines use their fuel injectors to control engine timing. Since diesel engines don't have spark plugs, it's necessary to inject fuel into the cylinder at the exact right moment. Any problem with the injectors or other parts of the fuel delivery system can lead to incorrect timing, causing your truck's engine to misfire.
Misfires will typically trigger warning codes, although they won't always tell you that the problem is fuel delivery related. However, the design of a diesel engine means that misfires almost always result from fuel issues or problems with the engine itself. In most cases, replacing faulty injectors will fix the problem.
3. White Smoke
White smoke typically indicates a severe problem with one or more of your injectors. If your truck is producing billowing white smoke, there's a good chance you have an injector that's stuck open. This problem is significantly more severe than a dirty or clogged injector, and it can cause rapid and severe internal engine damage.
As a general rule, treat billowing white exhaust smoke as a critical issue and get your truck to the side of the road as soon as possible. Attempting to drive another 10-15 miles to reach the next rest stop can result in critical engine damage, so it's imperative to shut the engine down as soon as you can do so safely.
For more information, contact a commercial truck repair service.