The reasons that prevent a car from starting are multiple, and one must proceed by elimination. Before using a specialist, small usage checks can solve the problem.
The lack of fuel prevents the engine from starting, this means that either:
The blockage of the fuel is due to a detached inlet pipe, or even fouling of the carburetor or injectors. Sometimes this is due to the quality of a fuel loaded with impurities (from a tank bottom), or to which an additive not recommended has been added. A fuel diluted with water clogs the fuel circuit, or even the fuel pump that ends up being damaged.
In addition, too much fuel in the carburetor also prevents the engine from starting because it is flooded.
Starter and combustion problems
A fault in the starter may also explain the problem: either the starter motor is faulty, or one of the pinions that make it up is no longer in place, or the teeth of these pinions are worn or broken. If it is not the starter, the problem can come from the shoke: badly adjusted, worn or blocked, it cannot produce and maintain the strength needed to start.
In addition, a spark plug (which provides the spark required for combustion) poorly tightened in its location, dirty or out of service, or poorly depressed may compromise starting.
If there is no power, due to a battery that is not charged or discharged, the starter and the various elements necessary for ignition (Delco or ignition coil, spark plugs and computer) cannot function. Moisture is also detrimental to start-up and serious wiping of the various electrical components is necessary. The problem can also come from a fuse that has blown, thus preventing the current from passing.