What To Do If Car Won’t Start When Parked In Sun?

If your car is not starting after standing outside in the sun for a long time, there could be many things that have gone wrong. Here are some of the main ones.

You may enjoy the warm summer sun, but it’s no friend of your car. Parking the car in the sun can sometimes spell trouble. It might happen that the car won’t start when parked in the sun. 

Excess heat can cause the fuel to vaporize when you park for longer hours in the sun. The battery can also become overheated because of exposure to high temperatures. 

Excess heat can also affect the starter motor and relay switch. So, it’s always to park your car under trees.


Car Won'T Start When Parked In Sun


Why Your Car Does Not Start When It’s Hot?

#1. Fuel Delivery

The fuel used in our cars can convert into vapor when you park in the sun. So, whenever you start your car after parking in the sun for long hours, then these vapors can create a problem for the fuel to flow through the relay lines.

Remember, the fuel used in your car can convert into vapor at 140 degrees Fahrenheit. While the outside temperature might not be as hot, inside the car, it can easily happen. This is because heat cannot dissipate from the car.

This issue commonly occurs in cars that are equipped with carburetors. So, older cars are more prone to the fuel vaporization problem when parked for a long time in the sun. However, you will not face this problem in cars with electronic fuel injection systems. 

So, if you have an old car and your car is having starting problems when you park for a long time in the sun, then it is better to wait for the sun to set or push it under a tree shade nearby. Allow the temperature of your car to drop, and the engine will start automatically.

However, if you have a newer model and it is not starting when kept for a longer time in the sun, there can be other reasons. You need to investigate the issue.

#2.Battery Overheating

Battery overheating can be another reason why your car is not starting.

A car’s battery consists of electrodes that convert chemical energy into electrical energy. This energy provides power to your vehicle. Additionally, the car’s battery stabilizes the voltages, which helps the engine to run constantly. 

The battery will function adequately till the temperature is 180 degrees Fahrenheit or less. But when the temperature exceeds 180 degrees Fahrenheit, the insides of the battery might start to corrode.

High summer temperatures can overheat the battery if you park in the sun for long hours. There is an electrolyte inside the car’s battery. When the battery gets overheated, the electrolyte can evaporate, causing heavy damage to the battery. So, overheating can decrease the life of your car battery, and you will be compelled to replace it with a new one.

If you think the problem can be because of the battery, then you can check without using any equipment. Turn on the headlights and AC of your car. If the headlights are dim or the AC is not working efficiently, your car has an overheated battery. Always park your car under trees to avoid battery overheating problems.

#3. Oil Change Needed

Oil plays a vital role in your car. It burns with fuel in the combustion chamber and helps lubricate the essential components so that it can run smoothly. 

The engine oil helps in removing excess heat from the car’s engine. So check your dashboard, and if the oil lights are switched on, it indicates that your car needs oil. Try adding oil to the engine and then check whether the car is starting.

You need to take your car to the nearest garage if it is still not working. They will detect the issue and correct it accordingly.

#4.Relay Connection Issue

Does your car not start after parking for a few hours in the sun? If yes, then that can be because of a broken electrical connection.

A relay switch helps to open and close the circuit, which starts the ignition process when you turn on the ignition. But sometimes, the relay does not switch on when exposed to high temperatures.

You need to open the bonnet and then the fuse box. You will see a key symbol on the fuse box; this is the ignition relay. Ask someone to start your car, and gently tap the ignition relay. If your car starts, then it is probably a relay problem.

Sometimes you may need to replace the relays with new ones. Relays are affordable and will cost you just about $20 to $40.The cost of the relays depends on the model of your car.

If your car does not start even after adding coolant or oil or checking the relay and battery, there can be other issues. The starting problems can also be because of the issue in spark plugs, fuel pump, fuel filter, or fuel pump relay.

Additionally, when you park under the sun, higher heat can affect the car’s starter motor. When the starter motor heats up, then it cannot draw the right amount of current required for running the car. So, you will face starting problems.


Car Won'T Start When Parked In Sun


How To Keep Your Car From Overheating?

#1. Always Park Your Vehicle In Shade

You should always park your car in the shade. It will help extend the life of the various vital components in it. If you usually don’t find a cool shady place to park your car, then it’s best to buy sunshades for it.

#2. Invest On Window Shades

You can put window shades on your car when compelled to park in the sun. Window shades will protect it from getting too hot. They will even help increase the life of various instruments in your vehicle.

#3. Window Film

Applying window film can help in keeping the car cool. They also help to protect you and your car from harmful ultraviolet sun rays.

#4. Leave The Windows Slightly Open

Sometimes you may have no other option but to park your car in the sun. Whenever you close all the windows and park your car in the heat for a long time, the windows will create a greenhouse effect inside. 

Glass is a good conductor of heat and can trap light in an enclosed space. This creates a hot chamber inside the car.

You should leave the windows slightly open so that it will not get overheated. The hot air will escape from the windows and keep the essential components inside cooler, and you won’t have to face starting problems after parking outside.

Additionally, if you have a sunroof, then open that also slightly. It will help in removing the heat from the car. But don’t open the sunroof too much so that anyone can enter inside your car.

#5. Check The Coolant Level

The coolant level is another crucial reason your car does not start after parking for a few hours in the sun. The coolant reservoir mainly comprises water. The water evaporates when you keep it under the sun for a long time. A low coolant level can damage your engine and create starting problems.

So, check the coolant level. If you find it’s too low, then add coolant. But never add coolant when the engine is hot.

#6.Think Of Replacing Your Battery

Have you used the same car battery for more than three years? If yes, then it will not provide proper power to the engine. Simultaneously it can create overheating problems when you park your car for long hours in the sun.

#7. Have Radiator Flush n A Fixed Time Interval.

Radiant flush or coolant flush must be done within a fixed time interval. Take your car to a good mechanic, who will flush all the old coolant and pour in new coolant.

 #8. Cover Some Parts Of Your Car With a Towel

If your car’s seats or the steering wheel is made of leather, it can heat up a lot after parking in the sun for a long time. You can cover the steering wheel and seats with a towel or blanket so it will not get heated up.

#9. Keep Mark On Temperature Gauge

You need to keep a mark on the temperature gauge of the car. It is usually found on the dashboard of the car. Remember, the needle should always point to the center. If it is pointed towards the hot, you need to switch off the engine and allow the car to cool down.

#10.Fresh Air Setting

You can set the air conditioner on fresh air for a few minutes. It will help in cooling your car faster. If you use the recirculation setting, you will actually move hot trapped inside the car.


Car Won'T Start When Parked In Sun


Frequently Asked Questions

#1. Is it bad for a car to be parked in the sun?

Yes, it’s bad for your car when you park for longer hours in the sun. When it is exposed to excessive heat for long hours, the essential components, like the battery, get heated up. Simultaneously the fuel can also evaporate. So, you might face starting problems when you park it in the sun.

#2. Does hot weather affect car battery life?

Summer heat significantly affects car batteries. High temperatures can cause corrosion inside the battery. The liquid inside the battery can evaporate, and ultimately, your battery will be dead. So, you may need to replace a new battery in your car.

#3. Why does my car not start after a long drive?

  • Alternator has overheated
  • Electrical connection issues
  • The fuel pump is not functioning properly
  • Problems in the engine, such as issues with the spark plug

#4. Why does my car start when it’s cold but not hot?

  • An air filter may get clogged with dirt and impurities
  • Battery problems like it have become overheated.
  • Fault in exhaust gas recirculation valve
  • Issues with your spark plug

Wrap Up

When excess heat is built inside the car, it can damage essential components, which can cause starting problems. So, always park your car in the shade, under a tree, or in other cool places.

Sometimes you may be compelled to park in the sun. You can keep the windows slightly open so that heat cannot get trapped inside your vehicle. Thank you for reading this article.

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Sean Mendez

Hi, I am Sean, a self-confessed petrolhead. I live in Boise, Idaho with a busy family of four and our energetic Labrador retriever. Thank you for visiting my website. You can find my email on the contact page.

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