Just a few questions about Yaris

[rafhelp]

This question relates to 2009 Yaris TR 1.33

1 - Does this car have a timing chain for sure? ( i thought with timing chain cars you can see the chain when you open the engine oil cap)?

2 - The manual says something like 0W-20 is the best engine oil...i used 5w-40 is that an issue. After adding 5w-40 and redex engin oil treatment the performance seems to have gone a bit worse with decreased MPG a bit.
So does 0W-20 really improve performance and fuel consumption?

[mrpj]

!. Yes. I depends on where the oil filler is located. If it's on the chain case, then yes, you'll possibly see the chain.
2. Use the engine oil that Toyota recommend in your manual, i.e. 0W-20 or if really necessary 5W-30. Don't use engine oil treatment, why would it be needed? I'm sure there's something in the owner's manual stating not to. Any improvement in "performance and fuel consumption" I suspect is negligible with 0W-20 oil.