P0359 code definition
The P0359 code indicates that a fault has been detected in one of the vehicle’s ignition coils, generally the number 9 coil. This code can also be associated with P0351, P0352, P0353, P0354, P0355, P0356, P0357, P0358, and P0360. Note that on some vehicles, the car’s computer may shut down the affected ignition coil. However, this is not true in all cases.
What the P0359 code means
A P0359 code means that there is a problem with one of the ignition coils on the vehicle’s engine. Many modern vehicles have individual ignition coils per cylinder. They’re mounted above or close to the spark plug, and the car’s computer is responsible for controlling each coil. The computer sends and on or off signal to operate the coils and create the spark needed to ignite fuel vapor.
What causes the P0359 code?
The P0359 code is set when the car’s computer does not receive a pulse from the coil during operation, or receives a pulse that is 10% greater than automaker specifications. The most common cause here is a failed or faulty ignition coil. While not considered part of normal maintenance, coils, like spark plugs, do wear over time and will eventually need to be replaced. The coil (or coils) could also be corroded or have suffered premature wear causing faults or failure. It could also be:
- A corroded ignition coil connector
- A short in the connector
- A faulty PCM (rare)
- Loose connection at the ignition coil
- Short or open wiring in the circuit
What are the symptoms of the P0359 code?
A number of different symptoms may be present with the P0359 code. The car’s Check Engine Light will turn on, and you may also experience one or more of the following symptoms:
- Rough idling
- Loss of power/performance while driving
- Engine difficult to crank
- Constant engine misfire
- Intermittent engine misfire
How does a mechanic diagnose the P0359 code?
The first step is to verify the code with a handheld OBD II scanner. The technician should clear the code and test drive the vehicle, checking if the code resets, as well as for consistent or intermittent misfires. If the misfire is not constant, the mechanic should inspect the wiring and connector to the ignition coil.
A loose connection or damaged wire can cause this problem. If the misfire is constant, the mechanic should check for signal to the affected coil using a scope to see the signal’s visual pattern. Alternatively, a voltmeter can be used to verify that the reading for the coil is between 5 and 20. If so, the coil is most likely faulty. If not, then there is a short somewhere in the wiring that must be located and repaired. With that being said, faulty or failed coils are the most common culprits here.
Common mistakes when diagnosing the P0359 code
The most common mistake when diagnosing the P0359 code is not determining if there is signal from the coil driver, which can indicate a short in the wiring. Another mistake is assuming that the problem is due to a need for a tune up. Even if a vehicle is past due for a tune up, thorough troubleshooting should be performed.
How serious is the P0359 code?
The P0359 code is serious, and should be repaired immediately. Misfires, even intermittent misfiring, can cause serious damage to the engine. In addition, performance and fuel economy will continue to suffer.
What repairs can fix the P0359 code?
The most common repair is replacement of a failed ignition coil. However, loose or damaged coil connectors are also relatively common. Shorts within the wiring are less common, but not unheard of, and should be ruled out before the coil is replaced.
Additional comments for consideration regarding the P0359 code
In some instances, the P0359 code can be accompanied by other codes related to other ignition coils. In this instance, the problem is often related to the wiring, or a problem with the computer.
Need help with a P0359 code?
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