WHAT TO DO IF A CAR ENGINE FAILS TO START
For every engine to crank and start, it requires four basic in variables: sufficient cranking speed, normal compression, sufficient ignition voltage, (there must be correct timing) and good quality fuel and a relatively rich air/fuel mixture at startup. So whenever there is a failure to start, you can rationally assume that your vehicle lacks one of these four essential variables. But the question is how do you know which one?
To find out the one, you first need to calculate the situation. If the engine doesn’t crank, it’s probably an issue with a starter or battery. Check mentally if the starter has been acting up in recent times (that is giving unusual noises or slow cranking, etc.). Is this the first occurrence where the engine has failed to crank or start, or has it happened before? Has the starter, battery or battery cables been changed in recent times? Might it be a worn part? Has the battery been running down? Could it be a charging problem? Could there be any other electrical problems? The answers to these questions could highlight what might be causing the problem.
Now if the engine cranks but refuses to start, it could be the absence of ignition, fuel or compression. if it was running fine but stopped suddenly? The most likely cause would be a failed fuel pump, ignition module or broken overhead cam timing belt. However if the engine has been getting progressively harder to start then you should consider the engine’s maintenance and repair history