Table of contents: The engine does not start ↓ Misfires ↓
Please also refer to Section Troubleshooting.
The control system components are very reliable. Failures are usually due to unreliability or contamination of contacts. Breakdowns in high-voltage wires most often occur due to contamination, moisture or damage to the insulation, and not due to a failure of the system components. Before concluding that a component is faulty, check its wiring.
Check the functionality of the high-voltage wire by removing it from the spark plug and bringing it close to the engine surface (watching for the presence of a spark), you can't. You risk not only getting an electric shock, but also damaging the control unit or ignition coil. If the engine is running unsteadily, never remove the wire tips from the spark plugs to determine which one is faulty.
The following checks should be performed if a fault is obvious (starter failure, misfires, etc.). Some faults are less obvious and may not appear because the engine management system has switched to emergency mode, ignoring signals from individual sensors and using. Such faults manifest themselves in increased fuel consumption, instability of idle speed, loss of power, detonation, etc. If you have detected such symptoms, contact a service station.
The engine does not start
Please note that if the anti-theft device fails, you will not be able to start the engine. Disconnect the device (refer to Chapter Controls and safe operation techniques).
If the engine does not turn over when the starter is engaged or turns over very slowly, check the starter and battery. Connect a voltmeter to the battery terminals and measure the voltage while the engine is cranked by the starter. Do not engage the starter for more than 10 seconds. If the voltmeter shows 9.5 volts or less, make sure the battery, starter and charging system are in good condition (refer to Section Charging and starting systems).
If the engine rotates at normal speed when the starter is engaged but does not start, check all high-voltage components of the ignition system.
Following the manufacturer's instructions, connect the strobe light and crank the engine with the starter. If the lamp on the strobe light comes on, voltage is reaching the spark plugs. Make sure the spark plugs are in good condition. If the lamp does not light, check the high-voltage wires (refer to Section Checking and replacing spark plugs. Checking the condition of high-voltage wires).
If there is no spark, make sure the ignition coil is working properly (or replace the coil with a known good one or check the resistance of the windings). If the fault is not detected, look for it elsewhere. If the engine starts after replacing the coil, the fault is detected. Do not rush to throw away the coil and buy a new one. Make sure the wiring is securely connected to the coil (the engine might not start due to an oxidized contact).
If the coil is OK, the fault may be in the powerful buffer output stage, which is part of the engine control unit, one of the engine control system sensors or an associated unit. In this case, a fault code should be recorded in the control unit's memory, which can be read from the memory.
Error codes can be read using special equipment.
Misfires
The most common cause of misfires is poor wiring contact with the terminals of the ignition coil or some sensor.
Turn off the ignition and make sure that all ignition system connectors are securely connected.
Check the high-voltage wires. Make sure that they are securely fastened at the intermediate fastening points and do not touch metal parts of the engine. If the wire touches metal and its insulation is damaged, then when the engine is running, the spark will not go to the spark plug, but to the ground. If even minor damage to the insulation of at least one wire is detected, replace the entire set.
You can make sure that the wires are fully functional by temporarily replacing them with known good ones.
When replacing wires, replace them one by one. This will avoid the risk of incorrect connection. Do not damage the wires during installation.
If the high-tension wires are completely intact, the cause of the misfire is most likely the ignition coil or one of the spark plugs. Install a new set of spark plugs (refer to Section Checking and replacing spark plugs. Checking the condition of high-voltage wires) or check the coil. Misfires may be caused by a faulty or dirty crankshaft position sensor (refer to Section Functioning of the control and injection system of a gasoline engine).
If checking the above mentioned components does not improve engine operation, read the fault codes from the control unit memory (refer to Section Controller for interfacing a personal computer with an on-board OBD II self-diagnostic system according to SAE (PWM and VPW) and ISO 9141-2 protocols and Specifications).