Fuel Pump for 2008 Chrysler 300: Complete Guide to Symptoms, Replacement, and Cost

The bottom line: If your 2008 Chrysler 300 is having trouble starting, stalling while driving, or making a whining noise from the rear of the vehicle, the fuel pump is likely failing and needs to be replaced. A professional replacement typically costs between $500 and $1,200, while a DIY replacement runs between $150 and $250 for the parts alone. This guide covers everything you need to know about diagnosing, purchasing, and replacing the fuel pump on your 2008 Chrysler 300.

Understanding Your 2008 Chrysler 300 Fuel Pump System

The fuel pump in your 2008 Chrysler 300 is an electric fuel pump module assembly located inside the fuel tank. It is not just a simple pump – it is a complete module that includes the pump motor, fuel strainer, pressure regulator, and fuel level sending unit all integrated into one assembly. This design means that when one component fails, you typically replace the entire module rather than individual parts.

The 2008 Chrysler 300 came with several engine options, including the 2.7L V6, 3.5L V6, 5.7L V8, and 6.1L V8. The fuel pump configuration varies slightly depending on your engine size and fuel tank capacity. Most 2008 Chrysler 300 models use either an 18-gallon or 19-gallon fuel tank, and the pump assembly is located on the left (driver's) side of the tank. The fuel pump is designed to deliver pressurized gasoline from the fuel tank to the engine, and it works with a small electric motor to ensure the right amount of fuel pressure reaches the engine.

Common Symptoms of a Failing Fuel Pump

Before you rush to replace your fuel pump, it is important to confirm that the pump is actually the problem. Here are the most common symptoms associated with a failing fuel pump in the 2008 Chrysler 300:

1. Hard Starting or No Start
Your engine cranks but struggles to fire up, or it does not start at all. This happens because the pump cannot generate enough fuel pressure to reach the engine. Many owners report that the car starts fine when cold but becomes increasingly difficult to start when the engine is hot. A failing fuel pump may not generate enough pressure to start the engine, and you might notice that the engine cranks but takes longer than usual to start.

2. Engine Stalling While Driving
The most dangerous symptom is when the engine suddenly dies while you are cruising down the road. This can happen without warning and may take several minutes before the car restarts. Some owners have reported this issue becoming progressively worse over months or even years. A failing fuel pump may cause the engine to stall unexpectedly, particularly at high temperatures or after extended driving, because the pump overheats and stops working properly.

3. Whining Noise from the Fuel Tank
A healthy fuel pump makes a quiet hum when you turn the key to the "ON" position. If you hear a loud whining, buzzing, or screeching sound coming from the rear of the vehicle, the pump motor bearings are likely wearing out. If you hear a loud whining or humming sound coming from the fuel tank area (usually near the rear of the vehicle), the pump is likely failing. The noise indicates that the pump is working harder than normal due to internal wear or contamination.

4. Loss of Power Under Load
If your Chrysler 300 feels sluggish when accelerating or struggles to maintain speed going uphill, the fuel pump may not be delivering enough pressure to meet the engine's fuel demands. A failing fuel pump may cause the engine to lose power when accelerating, climbing hills, or carrying a heavy load, which can be dangerous, especially when merging onto highways.

5. Check Engine Light Illuminated
The check engine light may come on with diagnostic trouble codes related to fuel pressure or fuel system performance. Common codes include P0087 (Fuel Rail/System Pressure Too Low) and P0231 (Fuel Pump Secondary Circuit Low). A diagnostic scan can confirm if the issue is related to the fuel pump or another component.

6. Surging or Hesitation
You may notice the car surging forward unexpectedly or hesitating when you press the accelerator. This is caused by inconsistent fuel delivery from a failing pump. The engine may "choke" or sputter as it tries to get enough fuel because the pump cannot maintain consistent fuel pressure.

7. Poor Fuel Economy
If you notice that your gas mileage has dropped significantly, a failing fuel pump could be the cause. The pump may be running inefficiently, causing the engine to burn more fuel than necessary.

8. Engine Overheating
In some cases, a bad fuel pump can cause the engine to overheat because the fuel system cannot properly cool the engine components. This is a less common symptom but should not be ignored.

Diagnosing Fuel Pump Problems

Before replacing the fuel pump, it is important to confirm that the pump is actually the problem. Here are some diagnostic steps:

Check the Fuel Pump Fuse. The 2008 Chrysler 300 has a 20-amp MINI fuse for the fuel pump, located in the rear power distribution center. If the fuse is blown, the pump will not receive power. Common causes of a blown fuse include a short circuit in the wiring, a damaged fuel pump drawing too much current, or a clogged fuel filter causing the pump to work harder.

Check the Fuel Pump Relay. The relay controls the power supply to the pump. If this component fails, the pump will not receive power even if the fuse is good. You can test the relay by swapping it with a similar relay from another system. The fuel pump relay will usually not fail when driving, but if your 300 isn't starting and the relay isn't activating, there won't be any voltage where the fuel pump harness connects to the pump.

Listen for the Pump. When you turn the key to the "run" position (without starting the engine), you should hear a brief humming sound from the rear of the vehicle as the fuel pump primes the system. If you don't hear this sound, it could be an indication of a bad fuel pump.

Test Fuel Pressure. Use a fuel pressure gauge to test the pressure at the fuel rail. For the 5.7L and 6.1L HEMI engines, optimal fuel pressure should be between 50 and 60 PSI at idle. If the reading falls outside this range, the pump may be weak or failing.

Check for Power at the Pump. Use a multimeter to test for power at the pump's electrical connector. With the key in the "on" position, voltage should read 12 volts. If voltage is present but the pump doesn't activate, the pump itself is likely defective.

Fuel Pump Compatibility and Part Numbers for Your 2008 Chrysler 300

When shopping for a replacement fuel pump, you will encounter multiple part numbers and configurations. The following information will help you select the correct pump for your specific vehicle.

For the 2008 Chrysler 300 with a 3.5L engine and 18-gallon tank, the correct fuel pump assembly is the left (driver's) side unit that fits 2005-2010 models. For vehicles with the 19-gallon tank, you need a different part number.

The Mopar OEM part numbers for the 2008 Chrysler 300 fuel pump module include:

  • 5136021AE – Fuel Pump/Level Unit Module Package, Left
  • 05136022AM – Fuel Pump/Level Unit Module Kit, Left, Primary (includes pump module, sending unit, and O-ring)
  • 68102700AE – Fuel Pump/Level Unit Module Package, Left
  • 05136023AF – Fuel Pump/Level Unit Module Package, Right
  • 68304753AA – Fuel Pump and Level Unit O-Ring
  • 52110282AA – Lock Ring

Important: Always verify the correct part number for your specific engine size and fuel tank capacity before purchasing. Using the wrong pump can lead to improper fuel pressure and poor engine performance.

Replacement Cost Breakdown

A professional fuel pump replacement for your 2008 Chrysler 300 typically costs between $500 and $1,200. This includes both parts and labor. The average national cost for a fuel pump replacement across all vehicles is roughly between $611 and $894, depending on the age of the vehicle.

If you choose to do the job yourself, the parts alone will cost between $150 and $250. Additional parts that may need replacement include:

  • Fuel tank hose: $20-$40
  • Fuel filter: $85-$100
  • Fuel pressure regulator: $160-$195
  • Fuel level sending unit: $1,100-$1,300

DIY Replacement Steps

Replacing the fuel pump in your 2008 Chrysler 300 is a moderately complicated job. Here are the basic steps:

  1. Relieve Fuel System Pressure. Use the Schrader valve (if equipped) to release pressure from the fuel system. A pressure gauge can confirm the system is safe to work on.

  2. Disconnect the Battery. Disconnecting the battery reduces the risk of accidental sparks during the repair.

  3. Drain the Fuel Tank. Remove as much fuel as possible from the tank before lowering it. A drain pan is essential for catching any residual fuel.

  4. Remove the Fuel Tank. Use a floor jack and jack stands to safely lift the vehicle. Remove the fuel tank straps using a 10mm or 12mm socket. Carefully lower the tank.

  5. Remove the Fuel Pump Module. Use a fuel pump module lock ring tool to remove the locking ring that secures the pump module to the tank. Without this tool, removal is nearly impossible.

  6. Install the New Pump. Place the new pump module into the tank, ensuring the O-ring is properly seated. Install the lock ring and tighten it securely.

  7. Reinstall the Fuel Tank. Raise the tank back into position and install the tank straps. Reconnect all fuel lines, electrical connectors, and hoses.

  8. Test the System. Reconnect the battery, turn the key to the "ON" position, and listen for the pump to prime. Check for leaks and verify fuel pressure.

Why Choose KEMSO for Your Fuel Pump Replacement

When it comes to replacing the fuel pump on your 2008 Chrysler 300, you want a part that delivers reliable performance and long-lasting durability. KEMSO offers high-performance fuel pumps that are designed as OEM replacements, meaning they meet or exceed the original equipment specifications. Every KEMSO fuel pump comes with a lifetime warranty, giving you peace of mind that your investment is protected.

KEMSO’s fuel pumps are built to handle the demands of your Chrysler 300, whether you have the 2.7L V6, 3.5L V6, or the powerful 5.7L and 6.1L HEMI V8 engines. The company is known for its commitment to quality and customer satisfaction, with a product line that includes fuel pumps for a wide range of vehicles. By choosing KEMSO, you are getting a part that is engineered for performance, reliability, and long service life.

Visit KEMSO today to find the right fuel pump for your 2008 Chrysler 300 and take advantage of their lifetime warranty. Don't settle for less when it comes to your vehicle's fuel system – trust KEMSO to keep your Chrysler 300 running smoothly.

Visit KEMSO Racing at: https://www.kemsoracing.com/


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