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  • Mitsubishi Fuso Authorized Dealer
    Established 1967
  • 1505 N 4th St. San Jose, CA
  • 408-263-7300
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Maintaining Your Diesel Fuel System

Maintaining Your Diesel Fuel System

Most heavy-duty trucks run on diesel. It offers efficient, powerful performance with less carbon emissions than gasoline. Regularly maintaining your diesel fuel system is essential to achieve maximum performance and keep your commercial vehicle running smoothly. Unfortunately, this task is far from straightforward. Diesel truck fuel systems vary considerably between models, making consulting the manufacturer service recommendations essential to safely performing common diesel truck service procedures.

Diesel Fuel System Cleaning

Regular fuel system cleaning is essential. Diesel fuel’s viscosity, which suspends dirt for longer periods, makes it more prone to contamination. Dirty, contaminated fuel causes most operational issues and can even result in engine failure. Rough idling, misfires, rapping, and puffing black smoke indicate problems with dirty fuel progressing to fuel injector or valve troubles. Fortunately, knowledgeable diesel truck repair technicians can easily identify these issues.

Removing Water and Air from the Diesel Fuel System

Like dirt, water and air in the diesel fuel system can cause serious problems. For this reason, manufacturers design most fuel systems to lock up and stop fuel flow with water exposure. It takes only a tiny amount of water contamination to cause engine misfiring or the need for major engine repairs. Filling your fuel tank at the end of each shift is another good way to purge humid air from the system.

Air trapped in the system is also detrimental, interrupting fuel flow to the engine. If you’re having a hard time starting your commercial truck, trapped air is a likely culprit. Air can infiltrate the fuel system through loose joints in the piping system or if you run your vehicle out of fuel. Bleeding your fuel system regularly and keeping your fuel tank topped off can prevent air contamination issues.

Maintaining Your Diesel Fuel System

Diesel Fuel Injection System Cleaning and Maintenance

Diesel injectors deliver fuel to the engine as a fine mist or spray. Dirty, clogged, damaged injectors impede performance. Unfortunately, fuel injection system problems can be challenging to diagnose. Wear and tear causes issues that typically worsen over time, making performance problems hard to recognize. Throttle hesitation, rough idling, and hard starting are common signs, but these fuel injector pump performance problems share many common traits with piston ring, valve, and cylinder liner issues. A compression test can uncover the culprit. Defense is key to prevention. To keep the system as clean as possible, change oil and replace fuel filters every 10,000-25,000 miles. Service your diesel fuel injection system regularly, at least every 36 months or 45,000 miles.

Keep your commercial truck running at peak performance, maintaining your diesel fuel system with help from the experienced service team at Diamond Mitsubishi Fuso. Our commercial truck repair shop is in San Jose, near Santa Clara, Mountain View, Morgan Hill, Gilroy, Sunnyvale, Fremont, and Milpitas (just off 101 and 680). Contact us at 408-263-7300 to schedule your diesel truck service and maintenance today.

diesel truck, fuel system, maintenance

Mitsubishi Fuso Authorized Dealer

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Mon – Fri: 8:00AM – 5:00PM

Weekends or After Hours by Appointment

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Diamond Mitsubishi Fuso

1505 N 4th St. San Jose, CA 95112

(408) 263-7300


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