"Service Engine Soon" Infiniti – What Can Be Wrong?

Many problems can trigger the "Service Engine Soon" message in your Infiniti. These range from minor problems you can handle to more complex problems that deserve the attention of a specialist.

Service engine soon message highlights

• Common reasons:oil change interval
• How to fix:change oil and reset the message
• Possible consequences:nothing will happen
• Priority level:Low
• Can you drive?Yes
• DIY repair:Possible
• Repair price range:$50-$200

The "Service Engine Soon" Message in Infinity: What Can Be Wrong?

It is common for drivers of Infiniti models, especially the more recent models, to see a "Service Engine Soon" message on the dashboard of their vehicles. The main reason for this is that the car needs a maintenance service that is due or there is a problem with the engine.

This maintenance service may include an oil change, low brake fluid levels, oil, and coolants. Other triggers can include worn-out spark plugs, a loose gas cap, bad oxygen sensors, a failing part of the engine, and many more. 

When the Electronic Control Module in your vehicle, otherwise known as your vehicle's onboard computer, notices a problem that it cannot correct, a computer in your vehicle turns on the "Service Engine Soon" light. This light is usually yellow or amber.

Upon turning on the light, the onboard computer stores a trouble code. Some call it an engine code. This code will tell the problem or problems that triggered the light on your dashboard.

After taking care of the problem, the light will usually go off after resetting itself. If, for instance, the light was triggered by a loose gas cap, it will automatically go off once you tighten the loose gas cap. 

When your "Service Engine Soon" message comes on, some symptoms to watch out for include rough misfiring, rough throttle response, unusual sounds, and a power reduction. The whole point of it is that there is a malfunction or failure in one or some parts of your Infiniti engine that needs to be serviced or replaced. 

However, below are some common problems that can trigger the "Service Engine Soon" message.

1) A Dirty Mass Airflow Sensor

A dirty mass airflow sensor can trigger the "Service Engine Soon" light. A mass airflow sensor determines how much air enters your vehicle's engine. It determines specifically the rate of mass flow of air into the engine, which helps the engine control unit deliver the right fuel mass to the engine. 

When your mass airflow sensor becomes dirty, your engine will run roughly, stall, and you may notice black smoke from your car's exhaust pipe.

To fix this problem, you'll have first to diagnose the problem to be sure that the dirty mass airflow sensor is responsible for the light. Ensure to clean the sensor with a Mass Airflow cleaner liquid only.

2) Failing Oxygen Sensors

A faulty oxygen sensor will give false catalytic converter efficiency readings, which can ultimately trigger the "Service Engine Soon" light. The oxygen sensor measures the amount of unburned oxygen in the exhaust. 

This information helps your car's Electronic Control unit determine a balanced air-fuel ratio for optimal performance. 

A bad sensor or heat-damaged wires can lead to failing oxygen sensors. Usually, the codes for this problem are P0138 and P0158.

3) Vacuum Leaks

Vacuum leaks in your Infiniti's V6 and aV8 engines can also trigger the "Service Engine Soon" light. The intake manifolds of an Infiniti car are complex. This means many spots are susceptible to an intake vacuum leak. 

When your car experiences a vacuum leak, a definite amount of air bypasses the normal engine intake tract. 

This will lead to a lean running condition, and you may experience rough idle, a reduction in power, and even hesitation when you hit the gas. 

The usual code for this problem is P0171 or P0174.

4) A Problem with the Automatic Transmission

A problem with the transmission can also trigger the "Service Engine Soon" light. When there is an electric problem with the transmission valve body, the gearbox goes into limp mode, triggering the "Service Engine Soon" light. 

The light alerts you to the underlying problem, which is commonly no more than a broken solenoid electrical connector. The usual code for this problem is P1757 or P0720.

After diagnosis, to confirm the problem, you can fix the problem by soldering instead of replacing the valve body unit.

5) Failing To Reset the Light After Performing the Required Maintenance

Another possible reason for this, especially when the required service has been performed, is the failure to reset the Service Engine Soon light after the repair.

After resolving whatever problems triggered the "Service Engine Soon" message, you may have to reset the lights. 

But it would be best only to reset after you have fixed whatever problems caused the light to come on in the first place.

Is the Service Engine Soon Message Different From the Check Engine Light?

Many drivers often get confused when researching the "Service Engine Soon" message on their Infiniti dashboard.

The Check Engine light usually looks like the image of your engine and will come up for many reasons. 

But the main job of the Check Engine light coming on is to put you on notice that something is faulty in your engine, and it needs to be detected. It essentially monitors the functions of the computers in your Infiniti and informs you of any malfunction, if there is one. 

The malfunctions that the Check engine lights aim to warn you about can be simple or complex. This can range from a loose gas cap to a more severe problem like a problem in your transmission or your Infiniti engine. 

The Service Engine Soon light, known among mechanics as the Maintenance light, differs from the Check Engine light in many other car brands. You will usually get the message on your dashboard screen, but it is not the same as the Check engine light. 

The Service Engine Soon alert aims to let you know that your vehicle is due for its regular maintenance service. This maintenance service may be as straightforward as changing the oil. But this will depend on the miles that your vehicle has covered. 

However, in many Infiniti car models, especially the newer models, the "Service Engine Soon" light also does the job of the "Check Engine" light. These newer models of Infiniti vehicles include the QX80, QX20, QX60, G37, G35, FX35, Q50, JX35, and many more.

"Service Engine Soon" Message Still On After the Performance of the Maintenance Service - Why?

Sometimes, drivers complain that the Service Engine Soon message is still on after they have performed the service. There is no cause for alarm. 

There are possible reasons for this. One of the main reasons for this is that the mechanic fails or simply does not remember to reset the message or the light.

Another reason is that the light may not have been illuminated at the time of the service. But it may come on soon after the service is done. Do not worry. You can consult your owner's manual on how to reset the light.

Alternatively, you can ask your mechanic to reset the Service Engine Soon light.

Resetting the "Service Engine Soon" Message

There is a long list of problems that can trigger the "Service Engine Soon" light in your Infiniti, which means a long list of codes can come up after the diagnostics. To reset the light, you'll have to look up what problem the code is hinting at and fix the problem.

Ideally, the codes will reset once you finish repairing or fixing the problem part that triggered the problem.

You want to locate the diagnostics port under the dashboard. Connect your code reader to the port and turn on the ignition. Your code reader should come on immediately after you turn on the ignition. From there, you want to access the codes from the main menu. 

Check out all the unresolved, current, and permanent codes and look up the codes to know what the problem is. After fixing the problem, go back to the main menu to clear the Fault codes. Press K to reset the "Service Engine Soon" light.

You must fix the problem before clearing the codes. Otherwise, the light will come back on in a short time after the problem triggers it again.

You may find the light still on after fixing the problem that triggered the light. Here's an old-school way to reset the light, which has worked for many Infiniti GX73 owners and many others.

You want to pop the hood and get to the battery. The battery will most likely be on the right-hand side of the hood. Get to the battery by taking off the cover, and with a 10mm wrench, remove the negative terminal. 

Take it off for about 30 seconds to reboot the computers in your vehicle. After 30 seconds, replace the negative terminal and tighten the nut back with your 10mm wrench.

Cover the battery and close the hood. Go back and start the car again, and you'll see that the light is gone.