I have a 1995 ssei, this just started happening in the last few days and tonight i was almost killed beacuse of the bonnie, my car power cuts in and out when driving the power will surge and then the radio and what not goes off and on. The dash does the exact same thing. Tonight it did it when i started my car after work the power just surged but it keopt alive. I was cruisng down the raod and pulled up to a redlight and out the old girl went, power and everything i was almost rearended. I had to push the old girl off the road looking like a moron. I popped the hood and played with the batery conections with a tool set that i always have, after a few minutes of tightening and what not the lights came back on and i fired it up, started driving and it surged again anybody have this problem. Its getting dangeroues and i need a car for work so hopefully somebody knows whats up, i just installed an indash dvd player but i dont think that could be the cause and the alternater or battery should not be an issue, beacuse the vehcile dynamics on my dash are reading 13.3v while the gass is on and a little lower at idle, hope theres something out there!

90% chance you have a loose or corroded battery cable connection. Either at the battery, alternator, or one of the grounds.

Also consider how you connected that in dash player. Did you properly insulate any exposed wires with electrical tape or connectors.

So thanks guys, so i could possibly have a bad ground or something? would you think it might have something to do with my car alarm? And if its a corroded wire were would i even begine the search i have the 95 gm service manuals would that be of an happy to me for this search, its really dangerous to be driving like this is the power cuts out while on the highway opr something im gonna get messed up, ill take a peak at the ground under the hood first. Thanks

Also check the MaxiFuse relay center. I had a Series I LeSabre that had a bolt there that had come loose, allowing it to corrode. The car would lose power just like you describe until I cleaned that up

Having just put the in dash player in..it'* possible a wire is pinched etc.. I would be jumping right on it and looking everywhere. As a mechanic the first question to ask yourself is, "was anything recently changed, or worked on". Take a look there and definately at the usual suspects.

I don't see a seperately fused cirucuit taking out the ignition.

I just encountered the same problem. I was going over a speed bump, when the recently installed cd player shifted a bit then cut off. A short ding, ding, ding and the security light flashed. The radio came back on and all was well for a while. The next day I went over the same speed bump and the same thing happened only this time the power to every thing went out and the engine seemed to cut of and on quickly. The service engine soon light came on but there was no sign of engine trouble. I drove home, and by that time the light went back out. I checked the codes and nothing showed up.
I decided to take it to the GM dealership and have their mechanics check it out. On the way a violent storm developed and right when the bottom fell out. Let me tell you 55 mph with no breaks no power steering and no visibility are not the kind of thrills I seek.
I put the car in the shop and now the mechanic is telling me he thinks its the alternator.

Was your problem ever fixed?

Is the security in the radio connected to th security of the vehicle because when it stalled the security light came on and I had to disconnect the battery for a minute before I could restart my engine.