Are you starting this car with temps lower then 0 degrees F? If not, then you should run a conventional 10w-40 in this DOHC engine. Its the 1.9L?
They will drink 5w30 or 0w30 because of the problems mentioned by previous posters.
If you aren't looking to repair the problem, and you wont be starting the car in the morning in temps lower then 0 degrees F, then you will cut your consumption in half by switching over to a conventional 10w40.
It will not hurt a thing.
Why did we switch away from 15w40? Personally I think the 15 winter rating is JUST to thick for most conditions, but 10w-40 is perfect for your situation.
Why did you do the switch again, your worried about winter starts?
All of a sudden everyone things a 10 winter weight oil is "thick" oil, you guys are nuts lol.