Why Does a Ticking Sound Occur After Replacing Spark Plugs?
2 Answers
Replacing spark plugs resulting in a ticking sound is due to the spark plugs not matching the vehicle. Relevant explanations are as follows: 1. The gap between the electrodes of a spark plug significantly affects its performance. If the gap is too small, the spark will be weak and prone to carbon buildup and leakage. If the gap is too large, the required breakdown voltage increases, making the engine harder to start and more likely to misfire at high speeds. Therefore, the spark plug gap should be appropriate, generally 0.7-0.8mm for battery ignition systems, with some spark plugs having gaps exceeding 1.0mm. 2. When replacing spark plugs, it is crucial to use spark plugs of the same size. During installation, using a self-purchased or vehicle-provided spark plug socket with a short handle can easily result in insufficient installation torque. If the torque is too low, the spark plug sealing gasket may not be fully compressed, leading to poor cylinder sealing. Over time, this can cause excessive cylinder temperatures and premature ignition.
I just experienced this - there was a ticking sound after changing the spark plugs, which gave me a scare. This is usually caused by improper spark plug installation, such as being over-tightened or too loose, making the spark plug gap unstable during engine operation and causing impact noises against the cylinder. If the electrode gap of new spark plugs is incorrectly adjusted or the model doesn't match, it can also produce ticking sounds during ignition. Thermal expansion difference is another factor, making it more prone to noise during cold starts due to uneven expansion. I recommend not delaying - drive to a professional shop as soon as possible to recheck installation tightness and gap. Otherwise, minor noises may develop into engine knocking, damaging cylinder walls or fuel efficiency. It's important to use OEM-spec spark plugs during regular maintenance and install them precisely using a torque wrench.
