P3409 OBD-II Trouble Code: Cylinder 2 Deactivation/Intake Valve Malfunction

Our certified mechanics come to you · 12-month, 12,000-mile warranty

SCHEDULE P3409 DIAGNOSTIC Get a fair and transparent estimate upfront
Red-stars EXCELLENT RATING ON

Cost of diagnosing the P3409 code

P3409 is a diagnostic trouble code (DTC) for "Cylinder 2 Deactivation/Intake Valve Malfunction". This can happen for multiple reasons and a mechanic needs to diagnose the specific cause for this code to be triggered in your situation. Our certified mobile mechanics can come to your home or office to perform the Check Engine Light diagnostic for $70.00. Once we are able to diagnose the problem, you will be provided with an upfront quote for the recommended fix and receive $30.00 off as a credit towards the repair. All our repairs are backed by our 12-month / 12,000-mile warranty.

Cars Estimate Credit towards follow-up repair Earliest Availability
Ford$70.00$30.00
Toyota$70.00$30.00
BMW$70.00$30.00
SCHEDULE P3409 DIAGNOSTIC Get a fair and transparent estimate upfront

Check Engine Light

P3409 code definition

The P3409 code is Cyl2 Deactivation/Intake Valve Control Circuit/Open. Cyl2 narrows the issue down to engine cylinder number 2. Other codes in the P3400 series may present concurrently with P3409, indicating a problem with another cylinder’s deactivation solenoid circuit.

What the P3409 code means

In an engine with eight or more cylinders, most modern vehicles are equipped with a feature which allows half of the cylinders to deactivate during times of light load operation. This enhances fuel economy and reduces emissions. The vehicle will only operate on all cylinders when needed – such as when starting, idling, or under heavier loads. If the MAF (mass airflow), MAP (manifold absolute pressure), or TP (throttle position) sensors send a signal to the ECM (engine control module) that is outside of the expected range, deactivation in one or more cylinders is affected and a P3400 code will set. In the case of P3409, this typically means that the intake control solenoid circuit has an open, a short, or high resistance.

What causes the P3409 code?

Several possible problems could cause the ECM to receive an inaccurate signal from the sensors, including:

  • A bad MAP, MAF, or TP sensor
  • Valve lifter malfunction
  • Low oil pressure caused by an obstructed oil passageway
  • A faulty cylinder deactivation solenoid circuit connection
  • A short in the solenoid wiring harness
  • Restricted fuel pressure
  • A mechanical problem in the engine
  • A faulty PCM or ECM (rare)

What are the symptoms of the P3409 code?

You may experience misfires and/or vibration when the engine is running, as well as an illuminated Check Engine light. The vehicle will only operate in the higher mode (V8, or V12 in the case of a 12-cylinder engine).

How does a mechanic diagnose the P3409 code?

Your professional will make sure the oil level and pressure are correct, and will verify the stored code using a code scanner. If there are other fault codes present, these should be addressed in the same order as the data indicates they occurred. Then the codes are cleared and the vehicle retested to be sure the code replicates. The technician will perform a visual inspection of the wiring and connections to check for corrosion or loose connectors. Next comes testing the cylinder deactivation solenoid with a scan tool. He or she will check the oil passages to see if there’s any sludge or blockage. If all of these tests turn out fine, the valve lifters may be inspected to see if they’re the source of the problem.

Common mistakes when diagnosing the P3409 code

It can be tempting to simply replace the deactivation solenoid and/or wiring, without checking for oil restriction, which is a common culprit in this issue.

How serious is the P3409 code?

This code may not seem serious at first, because the vehicle will likely continue to be operational. It can lead to further damage however, because the ECM turns off the faulty cylinder, causing the engine to run rough. It’s best to have the problem looked at as soon as you can.

What repairs can fix the P3409 code?

Repairing this code could involve one or more of the following:

Additional comments for consideration regarding the P3409 code

The engine cylinders are controlled by a complex network of components, which can make it difficult to narrow down the problem unless you’re a seasoned mechanic. Your professional has tools that provide more detailed information than most tools available to home users, allowing them to complete the diagnosis and repair much more quickly and efficiently. In addition, if the engine must be disassembled, this can be extremely time-consuming and labor-intensive unless handled by a pro.

Need help with a P3409 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.

trouble codes
Check Engine Light
P3409

Fast and easy Check Engine Light is on Inspection service at your home or office.

SCHEDULE P3409 DIAGNOSTIC
Get a fair and transparent estimate upfront

Recent Check Engine Light is on Inspection reviews

Excellent Rating


YourMechanic Check Engine Light is on Inspection Service

Average Rating

4.5/5

Number of Reviews

3,901

Rating Summary
3,566
166
43
25
101
3,566
166
43
25
101

AUDIE

30 years of experience
89 reviews
AUDIE
30 years of experience
Very helpful. Requesting him back in a week
2006 SUZUKI GRAND VITARA - CHECK ENGINE LIGHT IS ON - LAS VEGAS, NEVADA

Gerron

31 years of experience
122 reviews
Gerron
31 years of experience
Gerron called to see if he could come look at my car early. He arrived not long after and quickly diagnosed my car's problem. He was courtous and nice. I look forward to see him at our next appointment.
1997 NISSAN SENTRA - CHECK ENGINE LIGHT IS ON - BEAVERTON, OREGON

Ruben

13 years of experience
15 reviews
Ruben
13 years of experience
Great guy very knowledgeable and very helpful
2005 DODGE RAM 1500 - CHECK ENGINE LIGHT IS ON - TOMBALL, TEXAS

Chris

19 years of experience
1240 reviews
Chris
19 years of experience
Chris came early and didnt mind waiting for me. He thoroughly checked and researched all aspects of the issue. He is very knowledgeable and provided awesome customer service.
2009 FORD EXPLORER - CHECK ENGINE LIGHT IS ON - SANTA ANA, CALIFORNIA

More related articles

Veteran and Military Driver Laws and Benefits in Idaho
The state of Idaho offers a number of benefits and perks for those Americans who have either served in an Armed Forces branch in the...
Veteran and Military Driver Laws and Benefits in New Mexico
The state of New Mexico offers a number of benefits and perks for those Americans who have either served in an Armed Forces branch...
How to Avoid Back Pain in a Car
If you have back problems, sitting in a car for an extended period of time can be excruciating. Even without back problems, you could experience discomfort and soreness from...

Related questions

Q: What are some inexpensive possible solutions for a P2506 code?

A good way to protect yourself in a used car transaction is to request a pre-purchase vehicle inspection. That inspection, carried out by a certified Mechanic, dispatched to your location, will give you very specific data regarding any current problems...

Q: The computer for my car says it's EGR flow and there is no other symptoms. What you think?

Either the EGR (Exhaust Gas Recirculation) valve is stuck open or is closed and not opening. First try removing the EGR valve and cleaning it out. Then see if the engine light goes out and the engine runs good. If...

Q: Car stopped after rough idle

This is a common symptom of a faulty idle air control module. This module regulates the control of air being mixed with fuel at idle. When this is faulty, it will cause an imbalanced amount of air and fuel to...

How can we help?

Our service team is available 7 days a week, Monday - Friday from 6 AM to 5 PM PST, Saturday - Sunday 7 AM - 4 PM PST.

1-800-701-6230 · hi@yourmechanic.com