Q: Check Engine Light on code P3400 showing

asked by on

replaced all spark plugs, Throttle Body Sensor, Mass airflow Sensor, all four O2 Sensors. oil change every 5000 miles, using Synthetic oil.

Hello. This particular code indicates a performance issue with the cylinder deactivation system on bank 1. If you believe that all of the recent repairs are holding, then you may want to turn your attention the the solenoid and sensor of that deactivation system. To better understand what is causing the code, know that the PCM will deactivate cylinders to conserve fuel if the load is light on the engine. This is all controlled electronically with your engine input sensors.

If the engine is driving normally, it’s very likely an electrical issue. There may be an actual issue with the solenoids that control the flow of oil to those valves. There also may be an issue with the wiring to these solenoids. You can perform a visual inspection of these wires and terminals making sure they are clean, dry, and tight.

Was this answer helpful?

Need advice from certified mechanic? Get help now!

Over 1,000 mechanics are ready to answer your question.
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details
  1. Home
  2. Questions
  3. Check Engine Light on code P3400 showing

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Q: Josh I am buying a used cayenne Porsche 2014 with24,000MilesWhat will my main ten ever costs be

Hello....upon purchasing the vehicle your immediate repair, maintenance, and restoration (if applicable) costs will be highly dependent on the actual, as found, condition of the vehicle. It is really hard to say what those costs will amount to without thoroughly...

Q: jolting bad and stalling - 2009 Kia Sedona

Hi there. There are a variety of possibilities that could cause this. However, there are a couple of sensors the car has that are most commonly known for causing this kind of problem. A faulty mass air flow sensor is...

Q: Water pump problem

The water pumps leaking coolant is a common failure; the pump would need to be replaced to fix the problem. I recommend that you have a mechanic, such as one from YourMechanic, come to you and do a water pump...

Related articles

P0240 OBD-II Trouble Code: Turbocharger Boost Sensor B Circuit Range/Performance
P0240 code definition Turbocharger Boost Sensor B Circuit Range/Performance What the P0240 code means P0240 is an OBD-II generic code triggered when the Engine Control Module (ECM) detects the intake boost...
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...
P2428 OBD-II Trouble Code: Exhaust Gas Temperature Too High Bank 1
P2428 code definition A P2428 trouble code signifies that the PCM has detected a problem in the exhaust gas temperature sensor circuit in bank 1, which subsequently contains the number one...