Reliable ignition performance throughout the entire engine operating range is an essential factor in the efficiency of a catalytic converter.
Ignition by a spark of a small cloud of a fine air-fuel mixture is sufficient to initiate the entire ignition process.
The main elements of the ignition system include the battery, ignition distributor, ignition coils and switch, spark plugs, low and high voltage wires.
This ignition system uses a non-contact magnetic system, the elements of which are located inside the ignition distributor and include the distributor rotor, sensor coil, mechanical centrifugal ignition timing controller, vacuum ignition timing controller and switch. The latter is an electronic assembly, so care for the contact group, as in a mechanical interrupter, is not required.
In the electronic ignition system, the ignition voltage is more than 30 kV. Under adverse circumstances (high humidity in the engine compartment) voltage peaks can pierce the insulation and cause shock when touched. To avoid personal injury and damage to the ignition system when working with it, the following requirements must be observed:
- do not touch with your hand and do not disconnect the ignition wire when the engine is running or cranking the engine with a starter;
- disconnect the wires of the ignition system, connect and disconnect any measuring devices only when the ignition is off;
- you can not install an ignition coil designed for a system with a breaker;
- when heated above 80°C (when painting a car) do not start the engine immediately after heating;
- wash the engine only when the engine is not running;
- when carrying out electric welding work, it is necessary to disconnect the battery;
- It is forbidden to carry out work on the ignition system to persons with a pacemaker.
Checking the ignition system
Pic. 7.1. Using special pliers to hold the high voltage wire when checking for sparking
If the starter turns the crankshaft, but the engine does not start, disconnect the wire from the spark plug, bring it to a bare area «masses» vehicle for a distance of about 6 mm and ask an assistant to turn on the starter. While checking sparking, hold the high voltage wire with special pliers (pic. 7.1).
If sparking is not observed, check in exactly the same way for the presence of a spark in the next cylinder. The appearance of a spark and its subsequent disappearance is a criterion for the absence of sparking.
If a stable spark is observed, check the spark plugs and/or fuel supply.
If there is little or no spark, disconnect the ignition coil wire from the ignition distributor, bring it about 6 mm to the exposed area «masses» vehicle and check sparking in the same way as described.
If there is no spark, check the ignition coil.
If there is a spark, check the condition of the distributor cap and/or distributor rotor.
A further check of the ignition system must be carried out at a service center or workshop.