2003 Trailblazer P0300 Code After Rainy Weather and Thermostat Replacement
I own a 2003 Chevrolet Trailblazer. Today, while replacing the thermostat outdoors during heavy rain, my vehicle began running poorly and now displays a P0300 diagnostic code. I'm concerned whether the rainy conditions could have caused or contributed to this issue. The engine started misfiring shortly after the replacement, and I'm wondering if exposure to rain during the procedure played a role in triggering the fault.
Yes — it's likely related to a secondary ignition system issue. Similar to the advice not to wash an engine, moisture exposure can affect electrical components and spark plug performance. It's recommended to scan for diagnostic codes even if the check engine light is off, as underlying issues may still be present.