Mustang 940E Skid Steer: Troubleshooting Sputtering and Loss of Power

[MikePhua]

Introduction
The Mustang 940E is a popular skid steer loader used in various construction, landscaping, and material handling tasks. However, like any heavy equipment, it can experience mechanical issues. One common problem reported by operators is sputtering and loss of power, which can severely impact its performance. This article will explore potential causes of this issue, how to diagnose it, and solutions to restore the skid steer’s power.
Symptoms of Sputtering and Power Loss
Operators of the Mustang 940E have reported sporadic sputtering and a noticeable loss of power, especially under load. This issue can make the skid steer difficult to control and inefficient on the job site.
Symptoms:

• Engine sputtering or misfiring during operation.
  
• Loss of power when accelerating or under load.
  
• Irregular engine behavior, such as surging or stalling.
  
• Inconsistent operation of the hydraulic systems.
  

These symptoms can cause a noticeable decrease in performance, and troubleshooting the problem quickly is essential to prevent further damage.
Potential Causes of Sputtering and Power Loss
Several factors can contribute to sputtering and loss of power in the Mustang 940E. The issue is often related to the engine, fuel system, or air intake. Below are some of the most common causes:

1. Fuel System Problems:
   • The fuel system is a common culprit for sputtering and loss of power. Issues such as clogged fuel filters, air in the fuel lines, or a malfunctioning fuel pump can restrict fuel flow to the engine, causing it to sputter or lose power.
     
   Potential Fuel System Issues:
   • Clogged Fuel Filter: A dirty or clogged fuel filter can prevent the engine from receiving the proper amount of fuel, leading to sputtering or power loss.
     
   • Fuel Contamination: Contaminants such as water or debris in the fuel can clog injectors and cause uneven fuel delivery.
     
   • Faulty Fuel Pump: If the fuel pump is malfunctioning or not providing adequate pressure, the engine may sputter or stall under load.
     
   Solution:
   • Replace the fuel filter if it's clogged or dirty.
     
   • Inspect and clean the fuel tank for contamination. If necessary, drain the fuel and replace it.
     
   • Check the fuel pump’s pressure and functionality.
     
2. Air Intake and Filter Issues:
   • The Mustang 940E relies on a clean air intake to ensure proper engine combustion. A clogged or dirty air filter can restrict airflow, causing the engine to sputter and lose power.
     
   Symptoms of Air Intake Problems:
   • Reduced engine performance, especially during acceleration.
     
   • Decreased fuel efficiency.
     
   Solution:
   • Check the air filter for dirt and debris. Clean or replace it if necessary.
     
   • Inspect the air intake system for blockages, including hoses and ducts. Ensure all connections are secure.
     
3. Exhaust System Blockages:
   • A blocked exhaust system, such as a clogged catalytic converter or muffler, can lead to excessive backpressure, causing the engine to sputter and lose power. This is especially true under load when the engine requires higher output.
     
   Symptoms:
   • Reduced engine power and sputtering during operation.
     
   • Unusual exhaust odors or noise.
     
   Solution:
   • Inspect the exhaust system for signs of blockage or damage.
     
   • Clean or replace the catalytic converter or muffler if necessary.
     
4. Ignition System Malfunctions:
   • A malfunctioning ignition system can cause sporadic firing of the engine, leading to sputtering. Worn spark plugs, damaged ignition coils, or faulty wiring can contribute to engine misfires.
     
   Symptoms:
   • Engine sputtering or backfiring.
     
   • Irregular starting or stalling.
     
   Solution:
   • Inspect and replace the spark plugs if worn or dirty.
     
   • Test the ignition coils and replace them if damaged.
     
   • Check the wiring and connectors for corrosion or wear.
     
5. Battery or Charging System Problems:
   • Insufficient power from the battery or issues with the charging system can also cause sputtering and power loss. If the electrical system isn't providing enough power to the engine, it may lead to inconsistent performance.
     
   Symptoms:
   • Intermittent engine operation.
     
   • Low or inconsistent power delivery.
     
   Solution:
   • Test the battery voltage and charging system.
     
   • Replace the battery if it is old or not holding a charge.
     
   • Check the alternator and charging system for proper function.
     
6. Hydraulic System Issues:
   • If the skid steer’s hydraulic system isn’t functioning properly, it may not be able to generate the necessary power for the attachments, causing a drop in overall power and performance.
     
   Symptoms:
   • Slow or jerky hydraulic movements.
     
   • Unresponsive hydraulic attachments.
     
   Solution:
   • Check the hydraulic fluid levels and condition. Replace fluid if necessary.
     
   • Inspect the hydraulic pump and motors for wear or failure.
     

Troubleshooting Steps

1. Check Fuel System:
   • Begin by inspecting the fuel filter and lines for blockages.
     
   • Ensure that the fuel is clean and free from contaminants.
     
   • Check the fuel pump for proper operation.
     
2. Inspect the Air Intake System:
   • Replace the air filter if it’s clogged.
     
   • Check the intake hoses for leaks or blockages.
     
3. Test the Exhaust System:
   • Inspect the muffler and catalytic converter for signs of clogging or damage.
     
4. Evaluate the Ignition System:
   • Inspect the spark plugs and ignition coils.
     
   • Check for any faulty wiring or connectors.
     
5. Verify Electrical System:
   • Test the battery and alternator to ensure proper voltage levels.
     
6. Hydraulic System Check:
   • Inspect hydraulic fluid levels and replace if necessary.
     
   • Check for any leaks or damage to hydraulic lines.
     

Conclusion
Sputtering and loss of power in the Mustang 940E skid steer can stem from several issues, ranging from fuel system problems to engine and hydraulic malfunctions. By systematically troubleshooting each potential cause—fuel filters, air intake, ignition system, and hydraulics—you can identify the root cause and restore the skid steer to full functionality. Regular maintenance and timely repairs are crucial to preventing these problems and keeping the Mustang 940E running smoothly.