Car won’t start while it’s hot. After cooling it starts right up
Same as above
My car has 170686 miles.
My car has an automatic transmission.
Experienced mechanics share their insights in answering this question :
Hello. First we need to know if the vehicle is cranking over or not. If it is, then the heat is likely causing expansion and the electrical components are struggling. If the engine is not cranking over then the starter or battery are likely to blame. Both of these can be tested outside of the vehicle, and typically at your local parts stores. You need to replicate the symptoms in order to do other testing. Then with the vehicle not able to start, you will want to verify a few things. Make sure all the electrical connections are clean, dry, and tight. This includes the charging, starting, and battery ground wires. You will want to test for spark and make sure the ignition system is working correctly. You may even want to make sure the cooling system and temperature sensors are working correctly. Further testing is needed to find the cause of the starting issues.
How to Identify and Fix Common car Problems ?
Our sources include academic articles, blog posts, and personal essays from experienced mechanics :
The vapor pressure creates a gas bubble which impedes the flow of liquid fuel in the gas line causing reduced pressure. Vapor lock usually occurs during extremely hot weather conditions where the thermal expansion of gasoline is triggered.
The Santa Fe can have problems with starting in cold conditions, or when the engine is cold. This issue can be caused by one of two sensors failing: The temperature sensor or the coolant sensor.
That problem may suggest you need to clean the throttle body, replace fuel filter, replace air filter, replace spark plugs or have fuel injector problems (I had mine cleaned and balanced and it helped my start-ups alot).
The cold starting issue could possibly be caused by a failing fuel pump or even a temperature sensor. Heat increases resistance in electrical circuits, and it is possible that once the fuel pump has been running for a while, high resistance causes it to slow or stop.
A difficult start could be due to a number of things, from a dying battery to a faulty starter. But if your vehicle has a hard time starting after sitting for just a few hours, it can cause an extra layer of confusion. When this happens, one of the most common causes is low fuel pressure.
The most common reasons a Hyundai Santa Fe won`t start are a dead battery, an alternator problem, or failed starter.
“Cycle” the Key. Make sure the radio, headlights, heater, etc., are switched to “off,” so they aren`t pulling energy from your battery and engine. Now put the key in the ignition and turn it from the “off” to the “start” position about ten times. You`re “cycling the key,” which can help warm up the battery and starter.
Bad Sensors
One common culprit for this problem is the crankshaft position sensor, which measures the position and speed of the crankshaft. The computer uses the information from this sensor to know when to fire the spark plugs. If the sensor isn`t working, the spark plugs won`t fire, keeping the engine from starting.
Why won`t my car start but the battery is good? If your car won`t start but the battery is good, the most common cause is a faulty starter – though it could also be to do with your fuel. You may have insufficient fuel to get the car going.
There are many causes of hard starting but illustrative ones are a faulty engine coolant temperature switch (sensor), malfunctioning idle air control (IAC) valve, vacuum and EGR leaks, inadequate fuel delivery or pressure (clogged fuel filter, injectors), and contaminated or old gasoline.
Symptoms of a faulty cold start valve:
Engine stalling – After your engine starts, you may experience stalling while you drive. This will either occur at higher RPMs or when you take your foot off the pedal. Rough idle – Your engine may produce loud noises or even vibrations when you are idling.
Start the engine and, using the procedure described in section 20, listen to the cold start injector (located on the air intake chamber). You should hear a clicking noise, meaning the injector is functioning. If a clicking sound is heard, let the engine reach operating temperature and repeat the check.
The most common reasons a Hyundai Sonata won`t start are a dead battery, an alternator problem, or failed starter.
The engine compression is higher as the lack of heat makes ignition more difficult. Low temperatures cause engine oil to become more viscous, making it more difficult to circulate the oil. Air becomes more dense the cooler it is. This affects the air-fuel ratio, which in turn affects the flammability of the mixture.
Relevant Questions and Answers :
the most relevant questions and answers related to your specific issue
My car will not start Intermittently. I purchased a new battery 2 weeks ago and yesterday the car wouldn’t start. Got a jump and
ANSWER : The issue you are having is probably due to an intermittent fault in the starter motor itself or a deficiency in the starter electrical circuit, for example a large voltage drop due to a poor ground or a high resistance connection. These issues can be readily diagnosed and resolved on a mobile basis if you request a hard starting diagnostic. If you request that diagnostic, the responding certified mechanic will get this resolved for you promptly. Based on Toyota’s Factory Service Manual, the battery should not be disconnected if the vehicle engine is running. The battery acts as a large resistive voltage sink and consequently taking the battery out of the circuit, while the alternator is still running, can create a voltage spike on the car’s electrical system which is not good for voltage sensitive components such as the engine computer. If you have further questions or concerns, do not hesitate to re-contact YourMechanic as we are always here to help you.
Map sensor car won’t start up good ?
ANSWER : Your MAP sensor is an important input for your computer. It helps determine the load on the engine to calculate the correct amount of fuel to inject. It sometimes takes a few seconds for the vehicle to realize that the sensor is not producing a good signal.
At that point, it will use other methods to determine the fuel rate, such as pre-programmed fuel maps, throttle position, etc. I would suggest replacing the MAP sensor and retesting. If you would like to have it checked first, a certified technician from YourMechanic will be able to scan your vehicle and test components to determine the root cause of your starting issue before making a repair.
The car crank but won’t start
ANSWER : Hi there. This does sound like an issue with the wiring. If the check engine light is coming on every now and then this means that when it does not come on there is no power to the computer. This can be the wiring harness issue or an ignition switch problem. I would have to test for voltage to the computer when the problem is occurring to be able to find where the issue lies. If you need assistance, a certified YourMechanic technician can be dispatched to your location to inspect your vehicle’s non-start issue and suggest any necessary 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.
car hesitates when trying to start the car ,but when started then i shut car off and start again it will start right up
ANSWER : Hi there:
Sometimes when you have problems starting an engine initially it is caused by a restriction in fuel flow; caused either by clogged fuel injectors or the throttle body that needs to be cleaned. Once the fuel starts to flow and engine warms up, it’s much easier to start. However, it could also be an air filter, EGR valve or other components that causes this issue as well, which is why it’s best to have a professional mobile mechanic complete a car is hard to start inspection so they can pinpoint the source of this issue.
Car intermittently won’t start
ANSWER : Hi there. An intermittent no start condition, can be difficult to diagnose. Replacing the fuel filter would not hurt anything, especially if it hasn’t been replaced in the last 30,000 miles. Diagnostic procedures should be performed, at the time of no start, to confirm whether there is a loss of fuel, of spark or both.
Assuming the Check Engine Light is not coming on, leads me to believe the ECM (engine control module)/computer is not recognizing the fault. There are many possibilities for a no start condition: a faulty ignition switch, fuel pump relay, fuel pump, ignition coil, ignition module, crankshaft position sensor, camshaft position sensor.
Replacing components without diagnoses can be expensive and time consuming without resolution. I recommend having your vehicle’s intermittent no start diagnosed and repaired by a certified technician, such as one from YourMechanic, so that this can be repaired correctly.
Car won’t start after seeing engine hot turn a/c off warning light.
ANSWER : Hi there. Check the battery cables and make sure that they are tight and clean. Then check the battery voltage and see if it has a voltage of 12.6 or 12.4. If the battery is less than that, then the battery needs charged. If the battery has 12.4 volts or higher, then place a load tester on the battery and see if the battery can hold a charge when a load is applied. If the battery drops under 9.6 volts, then the battery is no good and needs replaced. If the battery drops to 11.5 volts, then there is a dry cell and possible a burned cell and the battery needs replaced. If you need further assistance with testing your car battery, then seek out a professional, such as one from Your Mechanic, to help you.
My car won’t start, neither does my auto. Start. Sometime it might start if I jump it sometimes it won’t.
ANSWER : Hi there. There are a number of issues that will make a car hard to start. Everything from the electrical system to the fuel system to the actual starter itself can be the problem. Finding the root cause of a hard starting engine can take some investigation. Ignoring a hard starting issue can further damage the vehicle, which will often result in a more expensive repair. You might want to have a mobile mechanic complete a car is hard to start inspection so they can pinpoint the source of the issues you’re having and recommend the right repairs be completed.
