Skip the auto shop - Our mechanics make house calls

P3458 OBD-II Trouble Code: Cylinder 8 Deactivation/Intake Valve Control Performance

check engine light

P3458 code definition

The P3458 code is stored when the measured values for cylinder deactivation mode are not within the range of manufacturer-specified values.

What the P3458 code means

In order to provide good fuel economy, vehicles are designed to deactivate certain cylinders during idling, starting, or other situations. Deactivation occurs when the intake and exhaust valves are prevented from opening by locking pins. During this deactivation, the MAF sensor, the MAP sensor, and the TP sensor are all measuring emissions values and voltage values related to the operation of cylinders. If the system has registered a command to deactivate, but the measured values don’t match what the system knows it should see in this situation, the system registers a fault, and sends the P3458 code to the PCM.

What causes the P3458 code?

There are a variety of issues that could cause the P3458 code to be stored within the PCM. These may include:

  • Poor electrical connection within the cylinder deactivation solenoid circuit
  • An open or shorted cylinder deactivation solenoid harness
  • Low oil pressure
  • Restricted oil flow
  • A mechanical condition within the engine

What are the symptoms of the P3458 code?

Typically, the only symptom that will be experienced when the P3458 code is stored in the PCM is the illumination of the Check Engine Light. Some vehicle owners may register a decrease in fuel economy.

How does a mechanic diagnose the P3458 code?

In order to diagnose the P3458 code, a technician will first scan with the OBD-II scanner and collect the data from the PCM. They should then check all of the solenoid wiring components and connectors, looking for any corroded, loose, shorted, or open components and repairing as necessary. When electrical issues have been eliminated, the technician will continue to go through other possible repairs for the P3458 code.

Common mistakes when diagnosing the P3458 code

The most common mistake when diagnosing a code like the P3458 is failure to clear the code after each possible repair, and performing a retest. The easiest way to repair an issue is often to duplicate the failure. If the technician remembers to perform this system clear after each possible repair, it will be much easier to pinpoint the issue.

How serious is the P3458 code?

The P3458 is a very serious issue that needs to be repaired as soon as it is detected. This code indicates that there may be a major malfunction in the vehicle’s ability to deactivate cylinders, which could cause a misfire or total engine failure.

What repairs can fix the P3458 code?

In order to repair the issue causing the P3458 code to be stored in the PCM, a technician will likely begin by checking the electrical components during their diagnostics. If these repairs do not clear the code, other possible repairs include:

  • Replacing or repairing the faulty solenoid
  • Replacing or repairing the solenoid harness
  • Repairing any issues causing low or restricted oil pressure
  • Replacing faulty MAF, MAP, or TP sensors

If the issue is related to an electrical problem in the engine, these repairs could take longer to diagnose and address. In extreme cases, the ECM may need to be replaced.

Additional comments for consideration regarding the P3458 code

The P3458 code is related to the operation of cylinder 8, which may be accompanied by fault codes for the operation of other cylinders, particularly if the issue is related to the common power source that the solenoid harnesses for each use. If there are multiple fault codes related to the operation of cylinders, a pinpoint test to discover the exact area of fault may be required.

Need help with a P3458 code?

YourMechanic offers certified mobile mechanics who will come to your home or office to diagnose and repair your vehicle. Get a quote and book an appointment online or speak to a service advisor at 1-800-701-6230.

The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details
Icon-warranty_badge-02

Skip the repair shop, our top-rated mechanics come to you.

At your home or office

Choose from 600+ repair, maintenance & diagnostic services. Our top-rated mechanics bring all parts & tools to your location.

Fair & transparent pricing

See labor & parts costs upfront, so you can book with confidence.

12-month, 12,000-mile warranty

Our services are backed by a 12-month, 12,000-mile warranty for your peace of mind.

Get A Quote

Need Help With Your Car?

Our certified mobile mechanics make house calls in over 2,000 U.S. cities. Fast, free online quotes for your car repair.

GET A QUOTE

More related articles

How Long Does a Vacuum Brake Booster Check Valve Last?
The braking system on your car requires a lot of pressure. The vacuum booster is one of the main sources of this pressure. This booster will take the pressure that...
Insurance Requirements for Car Registration in Kentucky
The Kentucky Transportation Cabinet requires that all drivers in Kentucky carry liability automotive insurance, or “financial responsibility” in order to operate a vehicle legally and maintain vehicle...
How to Transfer a Car Title in Idaho
In order to prove ownership of a car, you must have the title. However, when a car is sold, given away or inherited, the title needs...


Related questions

Q: Cut door trigger wire, reconnected it, and now the anti-theft is on and the car won't crank

Hello, thanks for writing in. If that was the only wire cut, the butt connector may not be sufficient to attach the wires together and they may have to be soldered. Some systems watch resistance readings through the circuit and...

Q: The car shakes and randomly cuts off while driving. The car has steam/smoke coming from under hood.

Hi and thanks for contacting Your Mechanic. If your engine light came on for the secondary air pump sensor, then it is possible that the secondary air pump (smog pump) has failed. The pump has oil in it and if...

Q: I have the check engine light on and checked for DTC's it says ECM set and CEM set

Hi there, thanks for writing in about your Volvo. There should be specific alpha numeric "codes" displayed on the Code Reader. Do you see/have those "codes"? These will help pinpoint any faults and assess the issue. I would recommend having...