Its very clear cut answer. If you want to save the money for some other things like house, investments, loan repayments, then using some money to make the car feel new is definitely a no brainer.

If you are complaining about the car in general, then sell it. No amount of money you spend on this old car is going to change anything if it involves your heart & mindset. And it could go as far as being looked down by your peers on wealth outlook or your dissatisfaction that the car is not maintenance free. Nothing and no one can change that for you. No one has answers for that.

I have a same 10 year old Myvi 1.3 Ezi. It does not cost a lot to make the car feel new. Seriously. If you keep looking at premium replacement parts, then it feels not worth it. Like tires. A piece of Silvertsones are RM 99 a piece. You can pay top dollar Continental for RM250 a piece. I'm not gonna debate about all that safety 4 contact patch shit as an excuse. If you're dumb behind the wheel, you deserve to die.