(Updated on July 12, 2021)
There is nothing more frustrating than a car that will not start. You will probably keep trying to turn the key as it is in the ignition system, but nothing will turn on. The engine will crank, but it simply will not start.
There could be many reasons as to why this is happening. It doesn’t always mean that something is wrong with your engine, though. There could be another component connected to the engine which is causing it to crank but not start.
A mechanic could always figure out what it is, but you could also figure it out yourself by understanding the various causes to look out for.
Top 5 Causes of an Engine That Cranks But Car Won’t Start
Most of the time, the cause of a cranking car that won’t start is very simple and affordable to fix. Depending on what the root cause is, if you let the problem go for too long, it could create a more serious issue with your engine that will cost you thousands of dollars to fix. Don’t let it get to this point.
Read also: Top 5 Causes of Car Overheating
Here are five of the most common causes of a car that cranks yet won’t start.
1) Fuel Issues
Believe it or not, there are a lot of people who have this problem because they don’t have enough fuel in their gas tank. This could be attributed to simply not refilling the gas tank or using the wrong fuel type.
If the fuel is contaminated and not filtered properly, you can experience a cranking engine that won’t start as well. So, always remember to use the right fuel type and to not let your fuel tank get under one quarter.
The problem may be related to a blown fuse or relay. For instance, without a working fuel pump relay, you’ll be able to crank the engine all day but you won’t get any fuel to the engine.
If the problem is related to a blown fuse or relay which is not letting the fuel injector put the proper amount of fuel into the internal combustion chamber, then a simple change of that fuse or relay should fix the problem. If the fuse blows a second time, you may have an electrical issue to track down.
Another issue related to the fuel is a fuel pump itself. If the fuel pump malfunctions or is going bad, it can cause the engine not to start even with the starter can cranking properly.
2) Battery Issues
If the engine cranks too slow, there might be a battery issue that is causing it. Perhaps your battery is low on power or there is corrosion on the terminals of your battery. Sometimes the terminals can be too loose as well.
Whenever these issues come up, you will have a cranking engine that does not start. Fortunately, it is inexpensive to fix these kinds of problems. Worst case, you buy a new battery which will cost about $150.
3) Computer Sensor Malfunction
The majority of modern vehicles have sensors in them which transmit information to the engine. Two of the main sensors for the engine are the camshaft position sensor and the crankshaft position sensor. These sensors tell the ECU where the main rotating components of the engine are, so the ECU knows when to open the fuel injectors and ignite the fuel mixture with the spark plugs.
If either one of these sensors were to malfunction, then the engine would not be able to start. You could also have a faulty throttle position sensor which would prevent the spark from being generated in the internal combustion cylinder.
If one or more sensors are bad, you will likely have a check engine light with a helpful code that will give you an idea of which sensor caused the problem. Check the code using a code scanner to help narrow down the scope of the problem.
4) Starter Motor
If you have a bad or failing starter motor, it will be unable to generate the number of amps necessary to turn on the ignition system and the fuel injectors. In the beginning, the engine will still crank but there may be a lot of strange noises being made while this happens.
If this problem continues to be left untreated, the engine will eventually stop cranking altogether. So, replace the starter motor right away when you realize this is the cause.
Starter motors will run you about $500 on most cars, which is much cheaper than having to replace your engine.
5) Security System
In vehicles that have a sophisticated aftermarket security system or an immobilizer, an error in this system can actually prevent the ignition system from working properly.
If you have looked into all the other possible causes and found that they weren’t present, then check with the company that installed your car alarm to see if it is working properly.