Q: What should you check for gasoline and diesel engines that turn over but won't start on 2000 Honda Prelude?
A: If your vehicle is an automobile with a gasoline engine that fires but will not start, look at the fuel level and top up if required, you need to examine the battery, possibly charge it, and check the battery terminals and cables, and finally look for problems with the fuel delivery system such as disconnected connectors or defective parts. Copper may also not allow starting if it has worn out or been mechanically damaged to beyond its normal limit, fuel contamination or where the ignition accessories have malfunctioned. If the engine does not crank up, check on the battery condition, operation of the neutral safety switch, the starter motor and the solenoid and look at the seized engine. And if the engine cuts out right after starting the scanner should check the ignition switch, wiring, intake manifold gasket for vacuum leaks, fuel rail pressure, and the ECM. If your starter motor rotates but does not turn the engine, then the chances are that the pinion gear and the ring gear are worn out. If one must turn the engine over a long time to start when cold one should look at battery, cables, fuel, tune up, coolant temperature sensor and engine management systems. If the engine is difficult to start when hot, the air filter, the engine grounds and the maintenance items should be checked. When the engine of a diesel turns over, but does not start, then check on the starting sequence, the glow plugs, air in the fuel system, the quality of fuel, compression pressure of the engine and the injection pump timing. Should the engine not crank over then inspect the battery, neutral safety switch, main starter parts or if the vehicle has seized up. If the engine stops after starting place the blame on limited fuel return line, glow plug failure, injection pump synchronization, low fuel output, fuel adulteration, and presence of air in fuel. If your starter motor spins but does not turn the engine over the issue may be related to the pinion gear and the ring gear.