Car missing and won’t stay running

The truck began missing very badly. It's hard to start and won't stay running.
Experienced mechanics share their insights in answering this question :
The most common cause of a vehicle misfiring is due to spark plugs and wires. This may not be the only thing going on with your truck, but would be the first thing to look at. A qualified technician, such as one from YourMechanic, will be able to diagnose your engine misfiring issue and perform any repairs that are required.

How to Identify and Fix Common car Problems ?

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From the spark plugs to the ignition coils, many different things can cause an engine to misfire. The most common causes of misfires are worn, improperly installed, and mishandled spark plugs, malfunctioning ignition coils, carbon tracking, faulty spark plug wires and vacuum leaks.
Ford Ranger P0300 Causes

Multiple misfires can be caused by many reasons from a faulty ignition system, fuel system, or internal engine failure. The most common reason for this to happen is faulty or worn-out spark plug coil packs, especially if it`s been a while since you had a tune-up.

Ignition system components, including spark plugs, plug wires, ignition coils and ignition timing are culprits as are lean air/fuel mixtures and mechanical issues within the engine. Worn piston rings, worn or broken valves and worn cylinder walls, as well as worn cam lobes can also contribute to the problem.
The P0302 error code indicates that cylinder two is misfiring and not receiving enough spark to its spark plug.
A clogged or failed exhaust gas recirculation or crankcase ventilation valve or faulty oxygen sensor can send the wrong signals to the computer and cause misfires.
Worn or fouled spark plugs are one of the most common causes of engine misfires. These small but crucial components deliver the spark that ignites the fuel in your engine. If they`re not working properly, your engine won`t be firing on all cylinders.
A misfiring cylinder can cause a proportional loss of power. For example, if one cylinder misfires in a four-cylinder engine, the car will lose 25 percent of its power.
Once the engine is cranked, you should look for blue sparks along the spark plug gap. If you can see blue sparks, this proves your ignition coil is working correctly. If you don`t see blue sparks or you see orange sparks, this is a sign that there`s a problem with your ignition coil.
Yes. While the damage may seem small initially, the longer you drive with a bad oxygen sensor, the worse the damage will become. Eventually, you may experience rough idling, poor acceleration, engine misfires, an illuminated check engine light, and failed emission tests.
Multiple reasons could trigger a code P0302 misfire, including a faulty spark plug, a bad ignition system, or a defective fuel injector.
A Bad Crankshaft Position Sensor

The crankshaft position sensor monitors the position and rotational speeds of the crankshaft. Without the crank sensor, the engine control module (ECM) wouldn`t know when to fire the fuel injectors and ignite the spark plugs.

Engine Misfires: A failing camshaft position sensor can cause your engine to misfire. Transmission Shifting Problems: The data sent to the engine control module can stop the transmission from shifting properly.
To avoid an engine misfire, it is important to keep up with regular maintenance. Make sure that you change your spark plugs and oil filter as recommended by the manufacturer. Additionally, inspect your vehicle`s ignition system components for signs of wear or damage, and replace them when necessary.
In most cases, replacing your spark plugs will solve a misfire problem. You should also check your ignition wires to make sure they haven`t corroded or worn out. These are also simple and inexpensive to replace. Your fuel system: If your ignition system checks out, then move on to your fuel system.
Vacuum leaks, especially those that are confined to one cylinder, will cause the engine to idle unevenly and possibly misfire. This is because the vacuum leak allows additional air to reach the affected cylinder, diluting its air/fuel mixture.
Engine misfires that are not repaired in a timely manner are the number one reason for damaged catalytic converters. The damaging conditions created by a misfiring cylinder of the engine can reduce the useful life of the vehicle`s catalytic converter by years or, even worse, meltdown the converter.
What kills ignition coils is location; being mounted in one of the hottest, most vibration prone and dirtiest parts of the engine. Modern ignition coils are typically located between two camshafts on the valve cover and exposed to dirt and oil.
Dirty or Old Spark Plugs

If your engine is misfiring, you may be able to fix the problem easily by replacing your spark plugs. Spark plugs are relatively easy to remove from engines and inspect for damage, and at less than $25 a piece, they are relatively cheap to replace, too.

The catalytic converter, or cat for short, is responsible for removing harmful emissions from the exhaust. If the two O2 sensors collectively sense that the oxygen levels don`t change significantly after running through the cat, it`s a sign of a bad catalytic converter.
A blinking Check Engine Light indicates a more serious misfiring problem. The P0302 trouble code is an indication that cylinder 2 is misfiring and is not getting the necessary spark to its spark plug.
When head gasket failure occurs between two or more cylinders, several symptoms are bound to result. The most common symptom in this case is a misfire, which would result from the leakage of compression between cylinders.
Various factors, including defective spark plugs and insufficient engine compression, can cause misfires.
If the ignition relay shorts, burns out, or otherwise fails while the engine is operating it will cut off power to the fuel pump and ignition system. This will cause the vehicle to immediately stall due to fuel and spark being cut off.
Some sensors change how the engine behaves when it receives information from the control module. The idle air sensor, coolant temperature sensor and EGR sensor all change things within the engine and fuel delivery system.

Relevant Questions and Answers :

the most relevant questions and answers related to your specific issue

Car shuts off, won’t stay running
ANSWER : The most common problem on this vehicle is the fuel pump and fuel pump module. If you remove the rear seat that the fuel pump cover is, on the passenger side. Listen to the fuel pump when it is running and when the car stalls your fuel pump will stop running about three to five seconds before the engine dies. Then you’ll know if the fuel pump is the culprit or not.

You can try and replace the fuel pump module first then replace the fuel pump. However, the fuel pump can short the module out, causing both to be bad and would need to be replaced. If you need assistance with this, feel free to contact a certified mechanic who can diagnose your starting issue firsthand and help you fix it accordingly.

Replaced alternator on car 2 times each time shows it’s charging 14v let car run for a little bit then test drive and car voltage
ANSWER : There are reports that the replacement alternators will not communicate with the engine computer and will not charge correctly. I recommend using only the manufacturer approved replacement part. It can be new or remanufactured but approved for use in the vehicle. Some lower cost alternators on the aftermarket will have charging problems since they will not communicate with the ECM on the vehicle and will stop charging.

As I’m driving, all my lights inside/out of the car turn off and the car still stays on. But when I turn the car off it won’t turn over
ANSWER : Hello there. The charging system on the car may not be charging the battery as you drive and the systems that keep the engine running are priority so the engine will stay running until the voltage drops below about 9 volts but the lighting and some other accessories may cut off above this voltage first. You should have the charging system tested to see if the alternator needs to be replaced.

When I crank my car it won’t keep running unless I keep my foot on the gas. As soon as I release the gas pedal my car stops running
ANSWER : The first thing you need to check for in a case like yours is air leaks. Check all the rubber parts and hoses under the hood for good condition and connection. The amount of fuel delivered to your engine is determined by the air that flows in and any air that gets in through a leak without being measured means less fuel being injected. There are of course a number of other possible causes; a failed Mass Air Flow Sensor for example, but they will require special skills and equipment to be examined. You can have this conveniently checked out by contacting Your Mechanic. They can send a technician to your home or office to check out your car and let you know exactly what it will take to solve your problem.

I just had my starter changed when I turned car on didn’t stay on. I had someone pass current and car turned on fine I drove car f
ANSWER : Hi there. It is quite possible that the starting issue you’re currently having with your Ford Focus is not related to the starter replacement. However, it could be due to might be due to your battery problem. When your battery does not have enough power to engage the starter, it also impacts other important systems critical to maintaining ignition, ranging from the ignition coils to fuel system components. It might be a good idea to have a professional mobile mechanic from our team come to your location to compete a car starts then dies inspection, so they can correctly diagnose this issue and ensure the right repairs are made.

My fans stay on when I turn my car on and my temperature gauge stays on cool and will not move up even when the car is running
ANSWER : Hey there. This can be caused by a number of things such as low coolant levels, a faulty thermostat, or a failing coolant fan switch.

As you may know, the coolant fan switch helps to maintain the proper coolant temperature by turning on and off at specific temperature thresholds. When this switch is not working properly, this can cause the fans to come on intermittently, all the time or sometimes not at all.

In your case, if they are on continuously, this may not allow the car to reach normal operating temperature as you have noticed. When this happens, you will notice a temperature spike and drop occasionally as the fan comes on and off. I would suggest having an expert from YourMechanic come to your home to diagnose your cooling system and pinpoint any needed repairs.

Car won’t start. The check engine light, battery light, and oil change light are coming on. I tried jumping the car and nothing happened. Why won’t my car start?
ANSWER : Hi and thanks for contacting Your Mechanic. If sometimes your vehicle will start with the new alternator and sometimes it won’t, then there is a loose connection in your charging system. Check all of the wires to the alternator and to the battery. Make sure that the battery cables are clean and tight. Make sure that the wires to the starter are clean and tight. A loose ground to the ignition system will cause the vehicle to not crank over. Check all of the ground wires from the battery to the starter. Make sure that they are clean and tight. If you need further assistance troubleshooting your no start situation, then seek out a technician, such as one from Your Mechanic, that can assist you.

Power steering loss, no belts are turning but the car is running fine. I also have a soft pedal. Whats wrong with my car?
ANSWER : I have only seen this situation once in my 30+ years and it turned out to be a broken crankshaft pulley. Belts are driven by the engine. The crankshaft pulley spins the belts, which in turn spin the air conditioner compressor, power steering and water pumps, and the alternator. The vehicle should be towed to your local repair shop and not driven. Without the water pump spinning to circulate the coolant, the engine will quickly overheat and result in more extensive damage.