Vehicle turns over but won’t start. Checked & changed some fuses & relays still nothing so I checked the wiring harness under the coil spark plug wire & no spark no power to it at all. Is also draining battery
Check for Injector pulse. Generally if you are missing both it is ECM/PCM related. Use a Fuel Injector Tester.
Fuel Injector Testing
A scan tool is the recommended method of troubleshooting injector-related problems, but the following tests can provide useful information in many applications.
- With the engine running, disconnect a wire of each injector, in turn. If no change in running condition is observed when one of the injectors is disconnected, the problem has been isolated to that cylinder.
- Check the resistance across the injector terminals. It should be about 12 ohms. If open or shorted, replace the injector.
- After removing an injector, apply 12 volts DC across the terminals. A “click” should be heard. If not, replace the injector.
Do NOT leave the injector connected to voltage for more than a couple a seconds. To do so will destroy the unit.
Ignition Coil Testing
Useful tests can be carried out with an ohmmeter.
- Disconnect the primary wires and the lead to the distributor.
- Check the resistance across the primary wire connectors. It should be about 1 ohm.
- Check the resistance between the one of the primary wire connectors and the high-tension lead. It should be about 12–15 kilo-ohms.
- If resistance is not within spec, replace the coil.
Checking secondary winding resistance
Testing in Place
- Disconnect the coil lead from the center terminal of the distributor cap and hold it about 1/2 ” from a good ground on the engine.
- Crank the engine. If spark occurs, the problem is probably in the distributor. If there is no spark, the problem is the coil or an upstream component.
Coil output is very high. Be sure to insulate yourself from the coil wire during the test.Checking coil for spark with component in place. For safety, insulate yourself from the lead