I Turn the ignition key and everything shuts off completely. then in 5 minutes the power returns back after disconnecting the negative cable. I turn the ignition key once again and completely shuts off the 2nd time.

whats wrong with the car?

i hear a crackling sound coming from the firewall. "crackle "crackle"

thx guys

 

What completely shuts off?

 

all power components..

 

You could just have a poor connection at the battery etc and you'll just have to narrow it down. remember, all accessories not involved in starting the car do not receive power w/key to start. Thus you need to specify the things in which you believe should be working and I guess you mean w/key to start or is it something else. It's your car and you need to supply the appropriate info for members to diagnose your problem.

 

are your terminals good and tight? Are you absolutely sure the battery is not backwards? I had this happen to me when I first got an RX7 I had the battery in backwards. The lights and everything worked but when I cranked, nothing would happen. The positive terminal should be CLOSEST to the driver, assuming that your setup is stock
.