Engine-CodesInfiniti – P0128 2005 Infiniti G35

P0128 2005 Infiniti G35 Code - Thermostat Function

Quick Answer

The P0128 code on a 2005 Infiniti G35 indicates that the engine coolant temperature is below the thermostat regulating temperature. Common causes include Faulty thermostat, Low coolant level, Stuck open thermostat. 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
P0128 2005 Infiniti G35 indicates Thermostat Function.
Common causes
Common causes include Faulty thermostat, Low coolant level, Stuck open thermostat.
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.
Table of contents Created and updated by William Orellana on Sep 10, 2024
💬 Need more help? Ask Auto Expert for instant answers — it's free!
AutoCodes App

Fix Your Car Smarter

Try the New AutoCodes App!

Get complete OBDII diagnostics, repair solutions, and cost estimates, plus AI chat support on demand.

AutoCodes App on Google Play

Code P0128 2005 Infiniti G35 Description

The P0128 code on a 2005 Infiniti G35 indicates that the engine coolant temperature is below the thermostat regulating temperature. This means that the engine is not reaching operating temperature within the expected time frame, which can lead to decreased fuel efficiency, increased emissions, and potential engine damage if not addressed promptly.

OBDII Code P0128 2005 Infiniti G35 - Thermostat Function
P0128 2005 Infiniti G35 Code - Thermostat Function

Common Causes of P0128 2005 Infiniti G35

  1. Faulty thermostat
  2. Low coolant level
  3. Stuck open thermostat
  4. Coolant leak
  5. Faulty coolant temperature sensor

Symptoms of P0128 2005 Infiniti G35

  1. Decreased fuel efficiency
  2. Engine running cooler than normal
  3. Slow or inconsistent heating in the cabin
  4. Check Engine Light illuminated
  5. Poor engine performance

How to Fix P0128 2005 Infiniti G35

  1. Begin by diagnosing the issue using a scan tool to read the trouble code and check the coolant temperature sensor readings.
  2. Inspect the thermostat to ensure it is functioning correctly and replace it if necessary.
  3. Check the coolant level and top it off as needed.
  4. Inspect the cooling system for leaks and repair any damaged hoses or connections.
  5. Clear the trouble code from the vehicle's computer and test drive to confirm the issue is resolved.

Cost to Fix P0128 2005 Infiniti G35

The cost of repairing a P0128 code on a 2005 Infiniti G35 can vary depending on the root cause of the issue. On average, replacing a thermostat can cost between $150 and $300, including parts and labor. Additional costs may apply if other components need to be replaced or if there are coolant leaks that require repair. It's important to consult with a trusted mechanic or dealership to get an accurate estimate based on the specific circumstances of your vehicle. Keep in mind that labor rates can vary, so it's advisable to shop around for the best price.

Tech Notes for P0128 2005 Infiniti G35

If cooling system is not leaking and the fluid level is OK, replacing the thermostat usually takes care of the problem.

When is the Code Detected?

The engine coolant temperature does not reach to specified temperature even though the engine has run long enough.

Need more information about the P0128 2005 Infiniti G35 code?

Need more information on how to fix the P0128 2005 Infiniti G35 code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the P0128 2005 Infiniti G35 code diagnosed by a professional: Find a repair shop in your area

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 P0128 2005 Infiniti G35 Code

1. What does OBDII code P0128 mean for a 2005 Infiniti G35?

The P0128 code indicates that the engine coolant temperature is below the thermostat regulating temperature.

2. What are common symptoms of a P0128 code in a 2005 Infiniti G35?

Common symptoms include the engine running colder than normal, poor fuel economy, and the Check Engine light being illuminated.

3. What are the possible causes of a P0128 code in a 2005 Infiniti G35?

Potential causes include a faulty thermostat, low coolant level, a malfunctioning coolant temperature sensor, or a problem with the cooling system.

4. How can I diagnose the cause of a P0128 code in my 2005 Infiniti G35?

Diagnosis typically involves checking the coolant level, inspecting the thermostat, testing the coolant temperature sensor, and ensuring the cooling system is functioning properly.

5. Can I continue driving my 2005 Infiniti G35 with a P0128 code?

It is not recommended to drive with a P0128 code, as it can lead to overheating and potentially damage the engine. It is best to address the issue promptly.

6. How can I repair a P0128 code in my 2005 Infiniti G35?

Repairing a P0128 code often involves replacing the thermostat, addressing any coolant leaks, checking and replacing the coolant temperature sensor if necessary, and ensuring proper coolant circulation.

7. What is the function of the thermostat in a 2005 Infiniti G35's cooling system?

The thermostat regulates the flow of coolant through the engine to maintain optimal operating temperature, ensuring efficient engine performance and longevity.

8. How important is it to address a P0128 code in a 2005 Infiniti G35?

Addressing a P0128 code promptly is crucial to prevent potential engine damage due to overheating and to maintain optimal engine performance and fuel efficiency.

9. Can a DIY enthusiast repair a P0128 code in a 2005 Infiniti G35?

Depending on your skill level, replacing the thermostat and addressing common causes of the P0128 code can be done by a DIY enthusiast with the necessary tools and knowledge.

10. How often should the thermostat be replaced in a 2005 Infiniti G35?

The thermostat in a 2005 Infiniti G35 should typically be replaced as part of routine maintenance or if issues arise, such as the triggering of a P0128 code.

Discuss the causes and fixes for P0128 2005 Infiniti G35 OBDII Code

Code P0128 2005 Infiniti G35 comments

No comments found for this page.