Things Needed for the Engine to Start
The starter motor turns the engine on, which needs a decently charged battery, a starter motor and a starter circuit in working condition. Fuel mixed with air is a necessary constituent for the engine to start. There also must be an effective spark to ignite the fuel and air mixture. The valves of the engine should be able to open and close at the correct time. There should be a proper compression in the cylinders. A normal compression needed to start the car is 120-170 psi. The engine won’t start if it is any lower than 70-80 psi. If the car doesn’t start, one or more of the above mentioned things are missing.
Conditions of a No-start Engine
The Starter doesn’t Crank
If there is no crank from the engine when you turn the ignition key, there is a problem in the starter motor which is unable to start the engine. A dead or low battery could be a possible reason for this. But if you are sure that the battery is fine, and the car is not cranking still, there could be many reasons for that. The most common problem is of the ignition switch which may be problematic. There can be a wrong or bad connection with the wires which control the starter motor. There is a ‘neutral safety switch’ installed in automatic transmission cars that allows the starter to operate only when the transmission is in ‘park’ or ‘neutral’ position. When the switch is faulty or shifter is not in the needed position, the starter won’t crank. Cars that have manual transmission have a switch at the clutch pedal that allows the car to start only when the pedal is pressed. If there is an issue with the clutch pedal switch, the starter won’t function.
Starter Click but no Crank
A discharged or low battery can be a reason when you only hear a normal click sound from the starter but no crank. If the battery is good, there can be defects in the starter solenoid, cables, or the starter motor.
Crank but the Engine doesn’t Start
There can be various issues if the engine doesn’t start after you hear a crank. This means your starter doesn’t have any problem. There can be issues with the fuel system like a bad fuel pump, fuel pump relay, or a clogged fuel screen. The engine’s electronic system also can be at fault with problems in the crank sensor, cam sensor, air flow sensor, power relay, or engine computer. There can be some ignition system defects such as a defunct ignition coil, switch, commutator, rotor, or distributor cap. There is also a slight chance of problems that include a broken timing belt or gear and low compression.
For preventing such car starting problems, one should ensure that there is enough fuel in the tank, a well-charged battery installed, and enough engine oil. Periodic servicing and checking of the car should also be done by an authorized professional mechanic.