Moody SVX

[DavieGravy]

My performance and engine quietness vary drastically from one driving interval to another. Typically, in the first period of driving, during the day, the car is quiet and powerful. Then, if I let it sit for 4 hours and drive it again at night, the engine's a noisey son of a b**ch and my power goes to hell.

Even though this is the usuall case, the first interval and the second interval often switch roles. So it really is quite random.

I don't think temperature's a factor, as it's usually colder at night. And from my understanding, cars usually run better in colder temperatures, right? In fact, I've had the car run worse in moderate temps than extremely cold temps.

Why on earth would it be doing this? Anyone have any thoughts?