Engine Not Running

An engine problem which affects timing may prevent the engine from starting or running. The camshaft drive belt and sprockets are responsible for timing the actions of the valves and the ignition system relative to the pistons and crankshaft. On diesel engines, the camshaft drive belt also drives the fuel injection pump. A worn belt and sprockets may jump teeth, throwing off all the engine's timing functions, and still appear to be perfectly normal. To check camshaft and ignition timing of gasoline engines, see 4.2 Camshaft Drive Belt and IGNITION. To check camshaft and injection pump timing of diesel engines, see FUEL SYSTEM (diesel). Other troubleshooting information for an engine which fails to start can be found in ELECTRICAL SYSTEM, FUEL SYSTEM, and IGNITION.

Table b lists symptoms of engine problems, their probable causes, and suggested corrective actions. The boldface numbers in the corrective action column indicate the heading in this section of the manual where the applicable test and repair procedures can be found.

Table b. Engine Troubleshooting