CatSkinner

Run a good quality oil and filter and change more frequently. We've said that doing a flush can frequently cause more problems than the dirt you're trying to remove. Additives are more designed for a maintained engine to keep it maintained, but as Logan said, today's quality oils make it moot to use an additive. If neglect has caused a poor condition in your engine, the correct answer is to pull the head and oil pan and clean it out.

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Prius repellant, just add gas.

Ghost

Alright, I'll have to look into doing that. Any suggestions for oil that I could start using until then?

CatSkinner

I generally use a synthetic high mileage, usually Valvoline or Mobil 1, but everyone has their own preference. I generally stay away from store brands as you don't know their source and can't guarantee the quality.

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Prius repellant, just add gas.