O2 sensor comes to mind - although usually, it's when the engine is cold, that you notice a bad one the most. But hey...throw some holy water on it, and if it doesn't catch fire, continue working on it

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It is a truism that almost any sect, cult, or religion will legislate its creed into law if it acquires the political power to do so. Robert A. Heinlein


09 Jetta TDI
1985 300D