Spark Test
NOTE:
Before performing spark test, ensure ignitor is properly grounded.
- Disconnect spark plug wires. Remove spark plugs. Install spark plug on each spark plug wire. Ground spark plug against cylinder block.CAUTION: To prevent gasoline from being injected, DO NOT crank engine for longer than 2 seconds.
- Crank engine and check for spark. If spark does not occur, check ignition coil, ignitor and distributor electrical connections.
- If electrical connections are okay, using ohmmeter, check resistance of high tension wires. Replace high tension wires if resistance is not within specification. See HIGH TENSION WIRE RESISTANCE table below. If resistance is within specification, proceed to step 4).HIGH TENSION WIRE RESISTANCE
Application Maximum Ohms All Models 25,000 Per Wire - Check voltage at ignition coil and ignitor. Turn ignition on. Ensure voltage exists at ignition coil positive terminal. If voltage exists, proceed to step 5). If voltage does not exist, check wiring between ignition switch, ignition coil and ignitor. Refer to the WIRING DIAGRAMS article for wiring circuit.
- Check ignition coil resistance. See IGNITION COIL RESISTANCE under IGNITION CHECKS. Replace ignition coil if resistance is not within specification. If ignition coil resistance is within specification, proceed to step 6).
- Check pick-up coil resistance. See PICK-UP COIL RESISTANCE under IGNITION CHECKS. Replace pick-up coil or distributor assembly if pick-up coil resistance is not within specification. If pick-up coil resistance is within specification, proceed to step 7).
- Check pick-up coil air gap. See PICK-UP COIL AIR GAP under IGNITION CHECKS. If pick-up coil air gap is incorrect, replace distributor assembly. If air gap is correct, proceed to step 8).
- Check ignition IGT signal from ECU. See appropriate DIAGNOSTIC TROUBLE CODE 14 chart in the TESTS W/CODES article. If IGT signal is okay, replace ignitor.