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P1688 Dodge Code - Internal Fuel Injection Pump Controller Failure

Quick Answer

The P1688 code for Dodge vehicles indicates an Internal Fuel Injection Pump Controller Failure. Common causes include Electrical faults, Wiring issues, Faulty fuel injection pump controller module. Severity is High - diagnose this code as soon as possible. Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.

What it means
P1688 Dodge indicates Internal Fuel Injection Pump Controller Failure.
Common causes
Common causes include Electrical faults, Wiring issues, Faulty fuel injection pump controller module.
Severity
High - diagnose this code as soon as possible.
Can I drive?
Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.
What is this?
Table of contents Created and updated by William Orellana on Sep 10, 2024
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Code P1688 Dodge Description

The P1688 code for Dodge vehicles indicates an Internal Fuel Injection Pump Controller Failure. This means that there is a malfunction within the fuel injection pump controller, which is responsible for regulating the fuel flow to the engine. The fuel injection pump controller plays a crucial role in the proper functioning of the vehicle's fuel system, as it ensures the correct amount of fuel is delivered to the engine for combustion.

OBDII Code P1688 Dodge - Internal Fuel Injection Pump Controller Failure
P1688 Dodge Code - Internal Fuel Injection Pump Controller Failure

Common Causes of P1688 Dodge

  1. Electrical faults
  2. Wiring issues
  3. Faulty fuel injection pump controller module
  4. Damaged fuel pump

Symptoms of P1688 Dodge

  1. Rough idling
  2. Engine misfires
  3. Hesitation during acceleration
  4. Stalling
  5. Difficulty starting the vehicle

How to Fix P1688 Dodge

  1. Begin by conducting a thorough diagnostic scan to confirm the P1688 code and identify the specific cause of the issue.
  2. Inspect the wiring and electrical connections related to the fuel injection pump controller for any damage or loose connections.
  3. Test the fuel injection pump controller module to determine if it is functioning properly. Replace it if necessary.
  4. Check the fuel pump for any signs of damage or malfunction. Replace it if needed.
  5. Clear the diagnostic trouble codes and test drive the vehicle to ensure the issue has been resolved.

Cost to Fix P1688 Dodge

The typical repair costs for resolving an Internal Fuel Injection Pump Controller Failure can range from $200 to $800, depending on the specific cause of the issue and the cost of parts and labor. It is important to note that diagnosis time and labor rates at auto repair shops can vary, so it is recommended to check with local shops for a more accurate estimate. Rates typically range between $80 and $150 per hour, with variations based on location, vehicle make and model, and engine type.

What does this mean?

Tech Notes for P1688 Dodge

P1688 code is typically cause from low fuel pressure. Since the overflow valve is closed at 10 PSI that means there is no cooling fuel to keep the electronics cool so now they overheat and start to malifunction (P1688). Hence why I highly suggests the 14 PSI as a minimum instead of the FSM minimum of 10 PSI.



Diagnosis And Testing



A rubber tipped blow gun with regulated air line pressure is needed for this test.

1. Clean area around overflow valve and fuel return line at injection pump before removal.

2. Remove valve from pump and banjo fitting.

3. Discard old sealing gaskets.

4. Set regulated air pressure to approximately 97kPa (14–16 psi).

5. Using blow gun, apply pressure to overflow valve inlet end (end that goes into injection pump).

6. Internal check valve should release, and air should pass through valve at 97 kPa (14–16 psi). If not, replace valve.

7. Reduce regulated air pressure to 10 psi and observe valve. Valve should stay shut. If not, replace valve.

8. Install new sealing gaskets to valve.

9. Install valve through banjo fitting and into pump.

10. Tighten to 30 N·m (24 ft. lbs.) torque.



Source: https://www.cumminsforum.com/forum/98-5-02-powertrain/450368-p1688-code-source.html#post4638821

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About the author: William Orellana is a Master Mechanic and Mechanical Engineer with over 30 years of experience diagnosing and repairing vehicles. Learn more about his background.

Frequently Asked Questions about P1688 Dodge Code

1. What are the common symptoms of OBDII code P1688 in a Dodge related to internal fuel injection pump controller failure?

The common symptoms include rough idling, engine misfires, loss of power, and difficulty starting the vehicle.

2. What are the potential causes of OBDII code P1688 indicating internal fuel injection pump controller failure in a Dodge?

The code is commonly triggered by issues with the internal fuel injection pump controller, such as wiring faults, electrical issues, or a malfunctioning controller itself.

3. How serious is OBDII code P1688 related to internal fuel injection pump controller failure in a Dodge?

This code should be taken seriously as it can lead to poor engine performance, decreased fuel efficiency, and even potential engine damage if left unresolved.

4. Can OBDII code P1688 in a Dodge be repaired without professional help?

While some DIY enthusiasts may attempt to troubleshoot and repair this issue, it is recommended to seek professional help due to the complexity of diagnosing and fixing problems related to the internal fuel injection pump controller.

5. How can a mechanic diagnose OBDII code P1688 in a Dodge indicating internal fuel injection pump controller failure?

A mechanic will typically use a scan tool to read the code, conduct a visual inspection of the fuel injection pump and related components, and perform electrical tests to pinpoint the root cause.

6. What are the possible repair options for OBDII code P1688 related to internal fuel injection pump controller failure in a Dodge?

Repair options may include repairing or replacing the internal fuel injection pump controller, fixing wiring issues, addressing electrical faults, or recalibrating the controller as needed.

7. Is it safe to continue driving a Dodge with OBDII code P1688 indicating internal fuel injection pump controller failure?

It is not recommended to drive the vehicle with this code active, as it can lead to further engine damage and potential safety hazards on the road.

8. How much does it typically cost to repair OBDII code P1688 related to internal fuel injection pump controller failure in a Dodge?

The cost of repairs can vary depending on the extent of the issue, the parts needed, and the labor rates of the repair shop. It is advisable to obtain quotes from different mechanics for an accurate estimate.

9. Are there any preventive maintenance measures to avoid OBDII code P1688 in a Dodge due to internal fuel injection pump controller failure?

Regularly servicing the fuel injection system, checking for wiring issues, and addressing any electrical problems promptly can help prevent the occurrence of this code.

10. Can resetting the OBDII system clear the P1688 code related to internal fuel injection pump controller failure in a Dodge?

While clearing the code may temporarily turn off the check engine light, it will not fix the underlying issue. It is crucial to diagnose and address the root cause of the problem to prevent further complications.

Discuss the causes and fixes for P1688 Dodge OBDII Code

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  • Yes i replaced the filter housing for filter and the new one came with the heater connected to housing

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