Smoke, flames or steam
Obviously if your car is on fire, you need to get off the road. Smoke or steam can be just as dangerous. If steam is coming out of your engine, it probably means that your coolant is leaking. If it’s a small leak, it might not be that bad, but if it’s a large leak, it can overheat your engine. Not to mention the steam can block your view and cause a fender bender. Pull over. Don’t open your hood to have a look though; when you open the coolant, it might spray up and burn you. Call the mechanic and have them fix it.
You should be familiar with the sounds your car typically makes. Turn off the radio now and then so you can learn what your car sounds like on a normal day. That way, if anything out of the ordinary suddenly pops up, you can take your car to the mechanic and prevent serious damage. If you hear any sudden loud noises, pull over and address it. You might have just run over something harmless in the road, like a milk jug or other trash, or there might be something seriously wrong with your car.
If you’re in pain, don’t try to hold out until you get home or to the hospital. Driving during a heart attack will put your life even more at risk. Even smaller concerns can still be dangerous – like a headache, or something in your eye.
Lack of Visibility
Sometimes storms come out of nowhere, and suddenly it’s pouring buckets and you can’t see the road. Don’t try to keep going, it’s useless. If it’s foggy, or your wipers are broken, or the spray from the road is blocking you from seeing the car in front of you, pull over.
No, it’s not okay to bend over and pick something off the floor or change your jacket while you’re cruising at 65mph on the highway. If your kids are fighting in the back, pull over. Anything can happen, and it only takes one negligent moment to cause an accident. Those few seconds you take to reach over and grab your CD, or take your hands off the wheel to slip out of your coat, could make the difference between a safe stop and a fender bender.