If your vehicle is malfunctioning, you are in trouble. It’s hard to imagine your life without a car in the US or in any other place where the speed of life is extremely high. So, when your car dies while idling, it can lead to very severe consequences. For example, you may get into accidents when you can’t go on time at the traffic light or when the car stalls right on the go.
In short, if your car dies and then restarts there are several possible issues like start-stop system problems, fuel pressure or ignition issues, and electrical failures. This problem requires a very thorough inspection of your vehicle and, in most cases, you will not be able to find and repair the issue on your own.
Nevertheless, I want to give you a quick overview of what can go wrong with the vehicle and how you can understand what the problem is. In the sections of this article, I will also try to explain to you what exactly you can do to try and solve the problem. But this will work only in some cases, of course.
Symptoms of the car stalling and then starting again
First of all, I need to make sure that we are on the same page. This isn’t a very common problem, so I want to list the symptoms and their variations to make sure that you will be reading relevant information.
So, I will be talking about the problems with the following symptoms:
- your car may stall just when idling;
- after that, it can or can not restart without you doing anything;
- this may also happen when you are driving and releasing the gas pedal;
- there is no check engine light, in most cases;
- the dash will most likely die, and the needles will go down and then get back to normal.
If at least two or three symptoms describe what you have in your vehicle, this article will help you find out the possible reasons and the ways to solve this issue.
What are the reasons for the car stalling and starting again?
There are about two dozen reasons I can come up with, but I will be talking about the most common ones. It doesn’t mean that your reason is exactly among the ones listed below. But, in most cases, you will find the answer in this article.
Here are the most common reasons for your car stalling and then restarting:
1. Start-stop function problems
Well, this is one of the most possible explanations for what’s happening with your car. First of all, you should check the automatic engine shut-off function. In some Japanese vehicles like Toyota, Lexus, Nissan, and Infiniti this function doesn’t really work that well. It means that sometimes, you will experience problems with engine stalling and not starting at intersections or some warning lights and messages will be popping up now and then.
The best solution, in this case, is to turn off the automatic engine shut-off function by pressing the “A OFF” button. It may be located near the engine start button, in the block of buttons and controls under the infotainment screen, or near the shifter. Press it and read the message saying that you’ve successfully deactivated this system. Try driving the car now.
If this didn’t help, the problem may be in a different system. Or you may need professional help in diagnosing your engine start-stop system.
2. Low fuel pressure
If the fuel pressure is the culprit of the engine stalling and then starting, the thing is in the fuel pump. Modern cars with direct or combined fuel injection have two pumps. The low-pressure fuel pump is located in the tank. The high-pressure unit may be located elsewhere. They both may fail.
You can also read about the common problems with your model of the vehicle and find out if one of those pumps commonly fails.
Also, the low or unstable fuel pressure may be a sign of a dying fuel pump, not dead yet, clogged fuel filter or line, and also problems with fuel injection. Low fuel pressure will not throw codes, in most vehicles, so you will not see the check engine light.
3. Bad air intake
It takes some fuel and some air to mix together to form the burning mixture. If the engine can’t get enough air to form this mixture, it will sputter and work poorly. One of the possible consequences is stalling. But then, it may restart because some more air entered the combustion chamber somehow.
You should check the air filter and then also the air pipes for some blockages or contamination. Another possible reason is the throttle. It may get stuck and eventually not let enough air into the combustion chambers.
4. Electrical problems
This is also one of the common problems that can happen to any car, especially after water damage. Electrical connections, fuses, wiring, control units, etc. – everything can fail and lead to all kinds of different glitches. If some wire connection goes off and then immediately goes back on, the engine may shut off and then restart.
Unfortunately, there is no simple way to check this. In most cases, you will need to get some professional help. With the help of code scanners and professional diagnostic equipment, specialists will find the actual problem. Doing this on your own is close to impossible because the car has hundreds of connections and wiring points that could malfunction and lead to such symptoms.
One more possible electrical problem is the alternator. If the voltage jumps, it means that the alternator is dying. But when it jumps down, the car may shut off if it can’t switch to the 12V battery immediately. Then the battery kicks in and the car may restart.
5. Ignition problems
In most cases, this issue will not be all about coils or plugs. If the situation was because of a faulty plug, one cylinder would misfire but the engine would keep running using all the remaining cylinders.
So, you should deepen the search for the problem and look at the ECU that sends the signals to the coils. It may malfunction or lose some contacts and the problem may show up. Solving the issues with the ECU is not that easy even for professionals, so I don’t recommend doing anything on your own. There is little chance you can succeed.
6. Transmission issues
One more possible reason is that the transmission gets stuck occasionally and makes the engine stall. But when it stalls, the gearbox gets unstuck and can rotate again. This is possible with all kinds of automatic and manual transmissions.
Unfortunately, this means that the transmission needs proper repair. It will be taken off, diagnosed thoroughly, and then repaired or replaced depending on the damage the mechanic will find inside.
What should you do if the car stalls and then restarts?
Most of us aren’t able to repair the car or locate the problem of the vehicle when it’s standing on the roadside. Given modern vehicles are very complicated from a technical point of view, trying to repair them on your own is not always a clever idea.
If your car stalls and then restarts, you may try the following:
- Stop the vehicle in a safe place. You should drive till you see a safe place for parking.
- Try to register any changes. If the car has changed its behavior, remember it or write it down.
- Look at the dash warning light. Are there any unusual lights or messages? Remember them.
- Let the car idle and see if it malfunctions. You can now calmly watch the vehicle and understand if it works well.
- Try resetting the ECU. You may disconnect the battery and wait for 5-10 minutes, then reconnect it back and try driving.
- Call for help. If nothing helps you, you should call the dealership or the trusted repair shop and plan your visit to the shop.
Is it safe to drive a car further if it stalls and restarts?
There are different possible variations of this problem and in some cases, it’s still safe to drive, but in some other situations, I would recommend not driving the vehicle. It can stall on the go, it can not restart in the middle of the road, and even cause accidents.
If you are in the dangerous part of the road and you still need to drive a bit, you need to turn on the emergency light and then go to the right side of the road. Better drive slowly – up to 10-15 MPH to avoid any dangerous situations. I strongly recommend you find a good repair shop near you and visit it for a quick diagnosis.
If you are driving on the highway and you can take the right lane with not so many cars on it, you can drive faster. Especially, if your vehicle doesn’t shut off on the go. In this case, be careful and don’t approach other vehicles too close. But anyway, don’t ignore the problem and have the car inspected as soon as possible.
Final thoughts
I wouldn’t say that the problem when your car stalls and then restarts is very common. But if this is what’s happening with your vehicle, you need to get some professional help. Also, you may try some DIY diagnostics tricks that I’ve described in this article. In some cases, a simple ECU reset or refilling your tank with more fuel will help. But more often, this problem shows up when there is a problem with the fuel supply, ignition, or the start-stop system.
Checking this and repairing the issue is possible in the dealership or in any trusted repair shop. But driving further with this problem in your car is not safe and you should avoid it. Though, you don’t need to call a tow truck and can carefully drive to the repair shop on your own.