2344776 | Genuine Paccar® Fuel Pump For MX13

A Fuel Pump 2344776 is a critical component in an engine’s fuel system that moves fuel from the tank to the engine at the correct pressure and flow rate so the engine can operate properly.

General Specifications

Purpose & Function

1. Delivers Fuel to the Engine

It supplies gasoline or diesel from the fuel tank to:

• Fuel injectors

• Carburetor (on older engines)

• High-pressure injection pump (on some diesels)

2. Maintains Proper Fuel Pressure

Engines need a specific pressure to:

• Atomize fuel correctly

• Run smoothly

• Start reliably

• Avoid stalling or hesitation

The fuel pump keeps this pressure stable.

3. Supports Engine Performance

A healthy fuel pump ensures:

• Proper power output

• Smooth acceleration

• Efficient combustion

• Good fuel economy

4. Prevents Air From Entering the Fuel System

It keeps the fuel line primed so the injectors get a steady supply.

Signs of a Bad Fuel Pump

1. Engine Hard to Start or Won’t Start

A weak pump can’t supply enough fuel pressure.

• Long cranking

• Starts only sometimes

• No start at all

2. Engine Stalling

The engine may stall:

• At idle

• While accelerating

• Randomly while driving
  This happens when the pump can’t maintain consistent fuel flow.

3. Loss of Power / Poor Acceleration

Common symptoms:

• Sluggish takeoff

• Hesitation

• Jerking or surging

• Weak high-RPM performance

The pump can’t keep up with fuel demand.

4. Low Fuel Pressure

• Measured with a fuel pressure gauge.
• Low pressure indicates a failing pump, clogged filter, or wiring issue.

5. Sputtering at High Speed

At highway speeds, the engine may:

• Sputter

• Misfire

• Momentarily lose power
  This is a classic failing pump symptom.

6. Whining or Loud Noise From Fuel Tank

A loud whine, hum, or buzzing inside the tank indicates:

• Worn pump motor

• Restricted fuel

• Failing bearings

7. Engine Misfires

A weak fuel supply causes cylinders to run lean, causing:

• Misfire codes

• Rough running

8. Poor Fuel Economy

Engine runs inefficiently when fuel delivery is inconsistent.

9. Check Engine Light

Common codes related to fuel pump issues:

• P0087 (Fuel Rail Pressure Too Low)

• P0089 (Fuel Pressure Performance)

• P0190–P0194 (Fuel pressure sensor range/engine performance)

10. No Sound from Fuel Pump During Key-On

• Electric pumps normally make a brief humming sound when the key is turned on.
• If silent, the pump or its relay/wiring may be bad.

About Paccar

PACCAR Inc is a global technology leader in the design, manufacture, and customer support of premium light-, medium-, and heavy-duty trucks. Founded in 1905 and headquartered in Bellevue, Washington, PACCAR is best known for its world-class truck brands: Kenworth, Peterbilt, and DAF.
PACCAR’s trucks are recognized for their durability, fuel efficiency, advanced engineering, and driver-focused technology. In addition to truck manufacturing, PACCAR also designs and builds diesel engines, and provides financial services, information technology, and aftermarket support to its global customer base.