AutoCodes – Infiniti – P0128 2004 Infiniti G35

P0128 2004 Infiniti G35 Code - Thermostat Function

Quick Answer

The thermostat is a component that blocks the flow of coolant to the radiator until the engine has warmed up. Common causes include Leaking or stuck open thermostat, Low engine coolant level, Insufficient warm up time. 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 2004 Infiniti G35 indicates Thermostat Function.
Common causes: Common causes include Leaking or stuck open thermostat, Low engine coolant level, Insufficient warm up time.
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.

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Code Popularity 6,474

How popular is this code, among other codes? Low

Repair Importance Level

Urgent (Diagnose now) (3 / 3)

Repair Difficulty Level

Intermediate (2 / 3)

What is this?

Table of contents Created and updated by William Orellana on Apr 21, 2019

Description
Step-by-Step Diagnostic Guide
Possible Causes
How To Fix
Tech Notes
Cost to Diagnose
FAQs
Comments
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Code P0128 2004 Infiniti G35 Description

The thermostat is a component that blocks the flow of coolant to the radiator until the engine has warmed up. When the engine is cold, no coolant flows through the engine. Once the engine reaches its operating temperature, the thermostat opens. The OBDII sets when the engine coolant temperature has not risen enough to open the thermostat even though the engine has run long enough. This is due to a leak in the seal or the thermostat open stuck.

OBDII Code P0128 2004 Infiniti G35 - Thermostat Function - AutoCodes.com — P0128 2004 Infiniti G35 Code - Thermostat Function

What does this mean?

What are the Possible Causes of the DTC P0128 2004 Infiniti G35?

Leaking or stuck open thermostat
Low engine coolant level
Insufficient warm up time
Faulty engine coolant temperature sensor
Engine coolant temperature sensor harness is open or shorted
Engine coolant temperature sensor circuit poor electrical connection

How to Fix the DTC P0128 2004 Infiniti G35?

Review the 'Possible Causes' above and visually examine the corresponding wiring harness and connectors. Check for damaged components and inspect connector pins for signs of being broken, bent, pushed out, or corroded.

What does this mean?

Code Tech Notes

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

What is the Cost to Diagnose the Code?

Labor: 1.0

To diagnose the P0128 2004 Infiniti G35 code, it typically requires 1.0 hour of labor. Rates vary by location, vehicle, and shop. Many shops charge between $80–$150 per hour; dealerships and metro areas may be higher, independents may be lower.

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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 P0128 2004 Infiniti G35 Code

1. What does OBDII code P0128 on a 2004 Infiniti G35 indicate?

The P0128 code on a 2004 Infiniti G35 typically points to a problem with the thermostat function.

2. What are the common symptoms of a P0128 code in a 2004 Infiniti G35?

Common symptoms of a P0128 code in a 2004 Infiniti G35 include the engine running cooler than normal, a decrease in fuel efficiency, and the Check Engine Light illuminating.

3. What can cause the P0128 code to trigger in a 2004 Infiniti G35?

The P0128 code in a 2004 Infiniti G35 is often triggered by a malfunctioning thermostat, low coolant levels, a faulty coolant temperature sensor, or a problem with the cooling system.

4. How can I diagnose the cause of a P0128 code in my 2004 Infiniti G35?

To diagnose a P0128 code in a 2004 Infiniti G35, you can start by checking the coolant level, inspecting the thermostat for proper operation, testing the coolant temperature sensor, and examining the overall condition of the cooling system.

5. What are the potential risks of driving with a P0128 code in a 2004 Infiniti G35?

Driving with a P0128 code in a 2004 Infiniti G35 can lead to poor engine performance, reduced fuel efficiency, potential overheating issues, and possible damage to engine components.

6. Can I repair a P0128 code in my 2004 Infiniti G35 myself?

Repairing a P0128 code in a 2004 Infiniti G35 may involve replacing the thermostat, addressing coolant leaks, testing and replacing the coolant temperature sensor, or flushing and refilling the cooling system. Depending on your mechanical skills, you may be able to perform some of these repairs yourself.

7. How much does it typically cost to fix a P0128 code in a 2004 Infiniti G35?

The cost to fix a P0128 code in a 2004 Infiniti G35 can vary depending on the specific cause of the issue and whether you perform the repairs yourself or take your vehicle to a mechanic. Costs may range from a few dollars for a thermostat replacement to a few hundred dollars for more extensive repairs.

8. How important is it to address a P0128 code promptly in a 2004 Infiniti G35?

It is important to address a P0128 code promptly in a 2004 Infiniti G35 to prevent potential engine damage, ensure optimal fuel efficiency, and maintain the overall performance and longevity of your vehicle.

9. Are there any preventive measures I can take to avoid a P0128 code in my 2004 Infiniti G35?

To help prevent a P0128 code in your 2004 Infiniti G35, it is recommended to perform regular coolant checks, adhere to the manufacturer's recommended maintenance schedule, and address any cooling system issues promptly.

10. How long does it take to repair a P0128 code in a 2004 Infiniti G35?

The time it takes to repair a P0128 code in a 2004 Infiniti G35 can vary based on the specific cause of the issue and the complexity of the repairs needed. Simple fixes like replacing a thermostat may take a couple of hours, while more involved repairs could take longer.