What are the common symptoms of failing spark plugs in a Toyota Prius?

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What are the common symptoms of failing spark plugs in a Toyota Prius?

Bad spark plugs can cause engine misfires, rough idling, poor fuel economy, and difficulty starting. What are the most noticeable signs that Prius owners should look out for?

Zarnish asked on 14 Feb 2025 16:33:10 pm

1 Answer

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Car Mechanic Expert - on 14 Feb 2025 16:41:03 pm

Failing spark plugs can cause several noticeable issues in a Toyota Prius:

Engine misfires: If the spark plugs are worn o r damaged, the engine may misfire, causing rough running o r loss of power.
Rough idling: The engine may shake o r vibrate more than usual while idling.
Poor fuel economy: A weak spark causes incomplete combustion, which can lead to higher fuel consumption.
Difficulty starting: If the spark plugs are worn out, the car may struggle to start o r take longer to fire up.
Loss of power: In some cases, you might notice reduced acceleration o r poor engine response.

If you notice any of these symptoms, it’s best to check the spark plugs to see if they need replacing.