90 Caprice, strange electrical problem.

I have a 90 caprice with a 305. Anyway what is happening is when I turn the key (meaning actually try to start the car, not just turning it to the on position) all the electricity goes dead and the car won't crank. The only way I can get the electricity back on is to wait a few mins and try again. I had the starter tested thinking the solenoid could be shorting out and sure enough when they tried to test it their machine went dead so I was really hoping that was the problem but after installing a new starter I still have the same issue.

Does anyone have any idea what could be causing this? When it first happened there were maybe 2 or 3 times when it would actually work if you tried again, now I cant get it to turnover ever. Electrical problems are definatly my weakest area and I have no idea where to look.

UPDATE: after cleaning all grounds and charging the battery the car will now start. There is another problem with the car that was happening before it refused to start. Anytime I put a fuse in the fuse slot for the radio it will instantly pop upon turning on the car. The first time it did it is when I plugged in an ipod fm transmitter to the lighter but now it has been removed and the fuses still pop instantly. Anyone know what could be causing this or where I should start looking?

Sounds like during the installation of the iPod transmitter, something may have happened to the lighter. The car is 19 years old, so things like this are common at this age as components get older and deteriorate. I'd look at the lighter and any wiring to it (possible signs of the outer insulation missing causing a short) or loose connections.Also look into the lighter where you insert the plug to see if any foreign matter, especially metallic in nature may have gotten in there. Something changed since the installation and removal causing a short somewheres possibly. I'd retrace my steps and look at everything closely to see if anything is out of the ordinary.

Thanks for your help. All electrical problems are solved and the car is finally drivable again for the first time since summer time! Now I just need to get around to fixing the speedometer cable and doing a brake job and everything will be wonderful.