What is the reason why the Volkswagen Lavida sometimes starts and sometimes doesn't when igniting?

[Summer]

The reasons why the Volkswagen Lavida sometimes starts and sometimes doesn't when igniting are as follows: 1. The battery is rusty or leaking. 2. The engine's spark plug is damp. Below is more information about the Volkswagen Lavida: 1. In terms of power: The Lavida uses a 1.6-liter engine derived from the Polo and a 2.0-liter naturally aspirated engine from Volkswagen's new engine platform. 2. In terms of configuration: The car adopts a three-spoke sports steering wheel, and high-end models are equipped with side airbags, a sunroof, perforated leather seats, a reverse radar, a Bluetooth system, and a luxury audio system with MP3 function.

[DeMicah]

My old Lavida also had this issue, and it turned out to be caused by corroded and loose battery terminals. Starting requires a high current, and poor contact can make it work intermittently. Besides the battery, worn carbon brushes in the starter can also cause this—sometimes it engages, sometimes it doesn’t. Another common issue is oxidized contacts in the ignition switch, which older cars are prone to after long use. Unstable fuel supply from the fuel pump is another frequent cause; clogged fuel filters or poor contact in the fuel pump motor can affect performance. I recommend cleaning the battery terminals first. If that doesn’t help, take it to a shop to check the electrical circuit, and have them inspect the starter relay and crankshaft position sensor while at it. Safety first—don’t push your luck.

[OTucker]

Last time my Lavida had the same issue, it took several days to diagnose. Poor contact in the starter motor's electromagnetic switch can directly cause ignition failure, especially in cold weather. Also check the fuel system - insufficient fuel pump pressure or clogged injectors may lead to poor fuel delivery. When the battery ages and can't hold charge, sudden failure to start is a warning sign. Another hidden problem: burnt contacts in the main relay causing intermittent control signals. It's wise to keep a jump starter in the car for emergencies. Regular spark plug replacement and throttle body cleaning can prevent issues, but wiring degradation in older vehicles is hard to avoid.

[DeVanessa]

As a car mechanic with twenty years of experience, I've repaired hundreds of Lavidas with this issue. The most common problem is oxidation of the internal copper contacts in the ignition switch, causing unstable connection when turning the key. Another frequent issue is a dirty starter motor, where carbon buildup affects conductivity. I remember one case where a customer's car was diagnosed with water ingress in the crankshaft position sensor connector, resulting in intermittent signals. Burned contacts in the fuel pump relay can also cause sudden power loss, though the car may restart afterward. I recommend checking the trouble codes, especially for P0335 sensor signal, and measuring whether the battery's starting voltage is below 10V. For older vehicles, prioritize inspecting aged wiring.