Skip to Content

Minivan Won’t Start When It’s Hot? Here’s Why And How To Fix It

When a minivan engine is exposed to extremely cold weather conditions, it can easily become hard to start. Nevertheless, hot engines too sometimes face these issues. Hot engines can become hard to start and many owners of cars and minivans do not know how to deal with this issue or why it happens. 

It becomes incredibly frustrating when they get struck in the house and are not able to leave on a hot summer day just because their vehicle’s engine is hot and it won’t start. 

This can happen not just when you have been using the vehicle for a while but also when the weather outside is extremely hot as well. 

Before understanding how to fix this issue when the minivan does not start due to a hot engine or hot weather, it is better to know what causes this issue in minivans first. 

What causes a minivan not to start when it’s hot? 

There are quite a few different things that could be causing a minivan not to start when it gets hot. I will mention the most likely reasons that this happens below. 

Fuel

The fuel could certainly be a contributing factor. If your engine becomes very hot, some vapors can obstruct it from running properly, which can make it harder for the fuel to circulate correctly. In turn, it will become hard for your minivan to start. 

However, newer models do not face this problem. 

The reason is that new minivans come with fuel injectors and since they keep the fuel at high pressure, there will not be any issues with the fuel not circulating due to hot weather or a hot engine. 

Do you feel that your vehicle is newer and has a fuel injector and still faces this issue? Then, you will have to look a little deeper to find the source of the issue.

Battery

The stranding of the minivan during hot weather can happen due to issues with the battery. The reason is that when the engine or weather is hot, your minivan’s battery will drain quickly just like it will in extremely cold weather. 

The reason is that batteries run on liquid and due to excess heat, this liquid evaporates. If your battery is more than a couple of years old changing it for a new one is a great place to start troubleshooting. 

Oil

Conventional motor oil can break down when the temperatures are high. So, experts generally recommend drivers to upgrade to thicker grade oils, particularly during hot summer months. This might not be a problem if your minivan is a newer model. 

Coolant

Another common reason for your minivan not starting when it is hot is that your vehicle is running low on coolant. When the coolant gets low, there are chances of serious damage to the engine of your minivan. So, if you find a warning light on your dashboard that looks like a thermometer, it is better to top up the coolant.

New Vehicle

In new automobiles, the engine temperature will continue to rise until it has been turned off. When this happens, the highest concentration of vapor gets circulated. This vapor can hinder engine performance to a great extent. So, without any doubt, when you drive your vehicle in a place with hot weather and turn off the engine recently and again when you try to start it, there might be issues with starting. So, when this happens, you will have to wait for some time and again try starting it. This move might work.

Seasonal weather changes

Seasonal weather changes might also be the reason for your engine not starting when it is hot. When seasonal changes in weather happen, refiners in your area will change from one fuel blend to another. For instance, when you take the case of gas refiners, they generally change from a higher volatility fuel to a lower variant when the season is heading into the summer. The reason is that hot weather can lead to the evaporation of fuels at a faster pace. 

Just in case, the refiners get back to a higher volatility fuel, while the minivans continue to be exposed to days with extreme weather conditions, this will lead to quick evaporation of the fuel. In turn, there will be a high level of vapor within the engine. This might also be a factor contributing to the hardness faced by your minivan to start.

How to fix it when a minivan does not start when hot?

I understand that it can be highly frustrating when your vehicle makes you stay at home on a hot summer day. So, your question here will be how to fix this issue that you are having. 

Here are a few things you can do to prevent and even to rectify this issue entirely. 

Check the coolant levels

Do you find that the coolant level is often very low? If so, it is time to top it up. The important thing you should remember here is that the best time to do this is when your minivan is cool. Otherwise, you can scald yourself. 

Further, you should remember that the coolant should not be overfilled as well. Also, before you top up the coolant, read the instructions given in the coolant container as it might have been specified that you should dilute the coolant before using it in your vehicle. One crucial tip to remember here is that coolant is highly corrosive. So, you should be very careful that you do not splash it on your vehicle’s paint. 

Also, you should ensure that it does not get on your skin.

Consider An Oil Change

If summer is approaching, you should consider switching to a thicker oil. Of course, your mechanic can guide you concerning this and some vehicles and mechanics recommend leaving the same oil thickness year around so always check your minivan’s manual as well. 

Check your battery

The ideal time to check your minivan’s battery is in the morning. At this time, you might have parked your vehicle overnight and it is always recommended to check the minivan’s battery after it has been sitting idle for a while. When you do this, you will get to know the resting voltage of your minivan. Also, it will give a good indication of the overall health of your minivan’s battery. 

You can find the battery on one side of the vehicle’s engine. 

When doing this, check whether you can gain access to the battery terminals. Most batteries will have plastic covers and you will simply have to undo some bolts. Now, take your multimeter and set its dial to 20 DC volts. Most multimeters come with black and red probes. You will have to place the black probe to the negative terminal of your vehicle’s battery and the red on the positive terminal. If you find that the reading is more than 12.6 volts, it means that your vehicle’s battery is charged. If the value is anything less than this value, you should get your battery charged by a mechanic or consider replacing it entirely. 

Conclusion

So, now you know what to do when the minivan does not start due to excessive heat! However, there are many other things that it could be if none of these work for you. 

Some people have reported it being the distributor cap, clogged air filter, faulty fuel system, engine control issues, starter, solenoid, and many more. 

Unless you are decently handy it might be better for you to try the simple things like a battery, starter, or solenoid and if that doesn’t work then call a mechanic since there are so many possible things that could be wrong.