My car is shaking at idle and is losing power in the low end service engine soon light is flashing.
I scanned the obd2 for my car and it gave me a p0304 which is a cylinder 4 misfire and I'm not sure where to go from here, do I replace the spark plug and the ignition coil. When I changed the spark plugs less than 2k miles ago I noticed oil in the spark plug hole above the plug and I'm not sure if that would have anything to do with the misfire or not so my question is do I replace the spark plug and coil or replace the leaky valve cover or spark plug seal. Thanks for your help
My car has 104579 miles.
My car has an automatic transmission.
Experienced mechanics share their insights in answering this question :
Engine misfires can be caused by many different problems and are generally caused by either a spark or fuel issue or in some cases, a combination of both. Spark related problems generally will result from things like ignition coils, crankshaft position sensor, spark plugs, spark plug wires or ignition modules not working properly. When the misfire results from a fuel related issue, this is commonly related to a lean fuel condition (lack of sufficient fuel supply to the motor). Fuel related misfires can be caused by many different things such as low fuel pressure, faulty or dirty fuel injectors, a faulty O2 sensor, a dirty or failing mass air-flow sensor, a faulty or dirty idle air control valve or a vacuum or intake leak. When the fuel supplied to the combustion chamber is insufficient, this results in an ignition (spark) that is igniting a less than balanced load of fuel and air. This results in a misfire or an explosion in the cylinder that is much less powerful than the other cylinders. This creates a loss of power that resonates throughout the motor additionally causing other problems with ignition and fuel timing. Due to the number of different things that may cause an engine misfire, the quickest and easiest way to diagnose this type of problem is to hook the vehicle up to a scanning tool which will download any potential fault codes that may have registered in the vehicle’s computer as a result of the poor running condition. I would recommend having an expert from YourMechanic come to your location to diagnose your misfiring problem.
How to Identify and Fix Common car Problems ?
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This is a common symptom of a plug or wire electrical current problem. Air or Vacuum Hose – Another common cause for engine vibration and power loss is when air or vacuum hoses come loose, begin to leak, or rupture. The three necessities for all combustion engines are air, fuel, and spark.
Faulty spark plugs and ignition coils are the most common reason for a running rough engine that causes shaking and a flashing check engine light. The shaking is usually from a misfire, and it`s common for the check engine light to flash for ignition-related codes. You might also notice a reduction in power.
One common cause of shaking while idling can be loose engine mounts. Engine mounts are the connections between your engine and your car — they keep your motor safely attached while dampening vibrations produced by your engine. When those connections wear out, you`re more likely to feel the vibrations.
There are a lot of things that can cause your car to chug and lose power. Dirty, old, worn out, clogged filters are a common cause of car sputtering and losing power. A clogged or failing catalytic converter can cause all kinds of problems for the engine, including sputtering and stalling.
Improperly functioning spark plugs cause an uneven burn of fuel in the engine, resulting in fluctuating RPMs and a louder noise. You might also experience increased vibrations of your vehicle while sitting idle or while traveling at low speeds. These vibrations originate from the engine and can shake the entire car.
A flashing check engine light is likely to indicate a misfire in the engine, so the car may judder and could sound rough. Continued driving could overheat and damage the expensive catalytic converter, which is part of the exhaust system. You should immediately drive to a garage, using the accelerator gently.
A flashing check engine light indicates a much more serious issue. Most often it means that the engine is misfiring and unburned fuel is getting into the exhaust system. This raises the temperature of the catalytic converter and can cause critical damage.
The most likely issue is that a component is clogged. A clogged fuel filter is the most common reason, although a loss of power in your car could also indicate problems with the fuel pump or fuel line. Impurities or debris may be blocking the system, which causes the loss of power in a car.
Faulty spark plugs result in an engine misfire due to incomplete burning fuel. An interrupted combustion process can significantly affect the engine performance. Unattended engine misfire may result in intermittent strange engine sounds, power loss, and engine knock.
Relevant Questions and Answers :
the most relevant questions and answers related to your specific issue
2012 equinox reduced power light engine light and traction light came on. Lost a lot of power got home and all light except engine
ANSWER : Your car has what is called a "safe mode" that will be engaged by the computer when it detects that something critical has gone wrong related to any of the major components in your engine chassis or power train. This may be related to a number of things, most of which should have been registered in the computer when the check engine light came on. I recommend having an expert from YourMechanic come to your location to inspect your check engine light and diagnose any codes registered by your vehicle’s computer.
Car not speeding up smoothly, service engine light on when first start driving and car vibrating
ANSWER : Hi There,
It sounds like you may have a dirty or faulty mass air flow sensor. The problem this can cause may also be compounded when the engine is cold due to the change in air density in cooler weather. The mass air flow sensor monitors air intake as it is mixed with fuel prior to being injected into the motor. This sensor relays information about fuel and air temperature, air speed entering the motor and many other things to the ECM which uses this to make adjustments to fuel supply to the motor. A dirty or faulty sensor can cause an imbalanced air/fuel load to be supplied to the motor which results in an over fueling or under fueling situation depending on the conditions. This type of inconsistent fuel supply to the motor may cause a hesitation, loss of power, a jerking reaction, potentially a bit of black exhaust smoke and typically a strong smell of fuel when this sensor is malfunctioning. I would suggest having a professional from Your Mechanic come to your home to diagnose and inspect your vehicle.
It sounds like you may have a dirty or faulty mass air flow sensor. The problem this can cause may also be compounded when the engine is cold due to the change in air density in cooler weather. The mass air flow sensor monitors air intake as it is mixed with fuel prior to being injected into the motor. This sensor relays information about fuel and air temperature, air speed entering the motor and many other things to the ECM which uses this to make adjustments to fuel supply to the motor. A dirty or faulty sensor can cause an imbalanced air/fuel load to be supplied to the motor which results in an over fueling or under fueling situation depending on the conditions. This type of inconsistent fuel supply to the motor may cause a hesitation, loss of power, a jerking reaction, potentially a bit of black exhaust smoke and typically a strong smell of fuel when this sensor is malfunctioning. I would suggest having a professional from Your Mechanic come to your home to diagnose and inspect your vehicle.
My car is shaking at idle and is losing power in the low end service engine soon light is flashing.
ANSWER : Engine misfires can be caused by many different problems and are generally caused by either a spark or fuel issue or in some cases, a combination of both. Spark related problems generally will result from things like ignition coils, crankshaft position sensor, spark plugs, spark plug wires or ignition modules not working properly. When the misfire results from a fuel related issue, this is commonly related to a lean fuel condition (lack of sufficient fuel supply to the motor). Fuel related misfires can be caused by many different things such as low fuel pressure, faulty or dirty fuel injectors, a faulty O2 sensor, a dirty or failing mass air-flow sensor, a faulty or dirty idle air control valve or a vacuum or intake leak. When the fuel supplied to the combustion chamber is insufficient, this results in an ignition (spark) that is igniting a less than balanced load of fuel and air. This results in a misfire or an explosion in the cylinder that is much less powerful than the other cylinders. This creates a loss of power that resonates throughout the motor additionally causing other problems with ignition and fuel timing. Due to the number of different things that may cause an engine misfire, the quickest and easiest way to diagnose this type of problem is to hook the vehicle up to a scanning tool which will download any potential fault codes that may have registered in the vehicle’s computer as a result of the poor running condition. I would recommend having an expert from YourMechanic come to your location to diagnose your misfiring problem.
Was driving on the expressway and my car started shaking, check engine light turned on, oil light turned on and off
ANSWER : Hello, thank you for writing in. Shaking and vibrating typically comes from a misfire, or poor engine performance. A lack of oil will absolutely contribute to these symptoms and amplify them, if not cause them to begin with. You want to turn your attention to the cause of the oil leak. If external (you can see the leaking oil), then you will want to trace the leak to the component which has failed. If the leak is internal (or the engine is consuming oil), the leak will be harder to find. It will also explain the poor engine performance due to excess oil in the combustion chamber. A head gasket is one of the main components that will fail and cause these issues. It is however not common for a vehicle this age to have these kinds of problems. You will also want to scan the computer, and see what codes are triggering your check engine light. These diagnostic tools will help you determine what system(s) is to blame for the malfunction. For more diagnostic help, contact our service department to schedule an appointment.
The VSA (!) light is on, engine light flashing, and it feels like the motor or car is shaking.
ANSWER : Hello, thank you for writing in. The VSA (vehicle stability control) warning light is telling you there is an issue detected with the system. The vehicle should be driven as minimally as possible. The issue may be directly related to the VSA system, or it may be related to one of the input sensors. The easiest way to help determine the problem is to scan the vehicle for diagnostic codes. They will point you in the right direction. Your owner’s manual will also have more information about the system. For more diagnostic help, contact our service department.
While driving on freeway truck goes into a limp mode, and the check engine light, abs light, parking break light, service brake
ANSWER : It is possible that you could be having an issue with your powertrain control module. This is somewhat of a common problem on many GM vehicles. I would recommend having your vehicle inspected by the dealership to determine if the powertrain control module is functioning properly. If not, a reflash of the powertrain control module may resolve the issue but often times it must be replaced.
Car loses power, sputters, shakes, jerks, stalls and the check engine light flashes and I cant drive over 15 like 20 mph
ANSWER : That type of very rough running, sputtering, no power is commonly caused by problems with the ignition system. The fuel system also needs to be checked to eliminate a fuel control problem as the source of this issue. Cam timing may also need to be verified to see if the timing belt has jumped out of time. When the Check Engine light blinks, it is telling you that the misfire is so severe that the catalytic converter can be damaged if you continue to drive it. It gets worse with the A/C on because that puts extra demand on an already struggling engine.
I suggest that you have a certified technician complete a comprehensive inspection on your vehicle to determine what repairs will be needed.
I suggest that you have a certified technician complete a comprehensive inspection on your vehicle to determine what repairs will be needed.
Check engine light refuses to go off after engine replaced
ANSWER : Hello there, you have a long series of issues going on with your 2013 Hyundai Sonata. If you keep getting a repeating oil light on than there is likely a fault in that system.
Since this fault has lasted after the engine was replaced it could be a oil pressure sensor, wiring harness fault, ECU fault, oil pump, oil strainer clogged, or low oil pressure.
To diagnose this issue properly you need a complete vehicle inspection to start from square one and identify the root cause of all this.
