lately, when I start the car, sometime all power is gone and I have to open the hood and touch the (+) battery cable connection, then power will be back. I tighten the connection but it will happen again.
does anyone have experience this problem?
Is it the alternator? or (+) battery cable..
any clue?

 

Taka,
there are two bolts per terminal. Which one are you tightening? Check the other bolt on top of the post to see if it is tight. Start with the basics

 

Taka,

Clean the two posts with baking soda mix with water then tighten both post. Negative and positive. Always take the negative out first if you want to disconnect the bat., installation is reverse (negative last)

 

I had this problem as well, I ended up replacing the battery but make sure the cable is tightly attached to the battery. I found out the cables in our car comes loose over the period of time.

Peter~

 

I just cleaned up connection area. I'll see if it'll give me anymore problems

 

After you clean any corrosion off the terminals, they sell battery terminal protector stuff at most auto parts stores.