What are the reasons why the car won't start in rainy days?
2 Answers
There may be several reasons why the car won't start in rainy days: 1. Short circuit: Since most of the vehicle's wiring and pipelines are concentrated in the engine compartment, driving through water may inevitably splash water on the internal wiring and pipelines. Over time, this can easily cause electrical short circuits and fuel line blockages, with the most direct fault being the car's failure to start. 2. Battery: In low temperatures, the car battery's output power decreases due to increased electrolyte viscosity, reduced permeability, and increased resistance, making it difficult for the starter to crank the engine to the minimum starting speed, thus affecting engine startup. Additionally, the low terminal voltage of the battery results in weak sparks from the spark plugs, and the increased resistance between electrodes due to the dense mixture makes it difficult to ignite the mixture, leading to engine starting difficulties.
Last time it rained, my car wouldn't start either, which was really annoying. I suspect water got into the ignition system, with rain dripping onto the spark plugs or ignition coils causing a short circuit, preventing spark generation and naturally making it impossible to start. It could also be that the battery is old, and the lower temperature on rainy days reduces battery performance, leading to insufficient starting current. Another possibility is water accumulation in the distributor cap affecting the ignition timing. I think preventing this is quite simple—try to park under a shelter when possible, or buy some moisture-proof spray to apply on electrical components. If this happens, don't panic; wait for the rain to ease or try push-starting. In short, checking the sealing of the electrical system before driving in the rain is very important.
