It is important for us to properly correct and diagnose misfires. Correcting this problem can be rather frustrating, if we can’t figure out why the car won’t start. Troubleshooting ignition misfires can be rather nerve wracking. The misfire could be caused by fuel or mechanical problems. Before delving deeper into the ignition issues, we should be able to rule out problems related to fuel system. It can be caused by collapsed fuel line, clogged fuel filter or weak fuel pump. Ignition problems could also be caused by vacuum leaks, worn throttle shafts and warped carburettor base. It is actually possible to miss the clogged main jet when we perform visual inspection. It may actually be blocked by clear plastic or even a grain of sand. We can use thin wire to ensure that the jet isn’t clogged. The overly rich exhaust may result into blown power valve. In modern cars, wiring system has become more complicated. Due to increased insulation quality, wires can now be tightly routed and bundled. Unfortunately, after quite some time, critical signals can be lost and corrupted and this will result in a misfire. In this case, it is a good idea to consider whether spark plug wires with solid core have induced unwanted signals for the ignition amplifier. This causes the amplifier to trigger the ignition at the wrong time.
Misfire could also be caused by poor connection on spark plug wired and end of coil. Problems may also occur when connectors aren’t seated on the plug or if they have bad crimps. The plug wire boot may have some moisture trapped and the wire can be blown off when the steam suddenly turns to steam. Corona can be reduced with a thin film of oil and it will also make sure that the moisture can escape easily. To prevent misfire, we should make sure that spark plug wires are properly separated; they shouldn’t run parallel to one another. Problems can also occur when the coil is mounted much closer to the amplifier.
Overall, weak misfire can result in poor performance, reduced power and eventually misfire. Malfunctioning alternator and low battery may also cause misfire. Connectors that are too small and poor power connection can limit ignition outputs. It is possible that master switch isn’t rated for the standard and it causes low current flow, causing poor operation. When diagnosing the car for misfires, mechanics usually use voltmeter. Car owners could also use voltmeter to determine whether misfire is about to happen. A 12V misfire could indicate that the car lacks reserve power. We should be able to remedy this problem by installing a new alternator, using 16V battery, retarding the timing and reducing the spark plug gap. A 14.5V misfire can be rather more complicated and we should check whether the tach gets erratic or fluctuates. It should be noted that misfire problems develop over time and there are some indications that we can see before misfires occur.