Originally Posted by Damageinc
It could possibly be the computer chip in the key,if so equipt. I have seen this problem before in other GM vehicles with this type of security.
This is a common problem for cars with resistors imbedded in the key. When you use your key an electrical current travels through that resistor and is changed and goes out another wire back to your bcm, In your case the wires are coming loose explaining why it works some of the time. This can be fixed by yourself easily, You could buy a whole new ignition switch and have it installed which would cost around 300 dollars, or you could go to your local radio shack, or whatever you have that is similar have them test the resistance on your key using ohms or you can look online for oldsmobile key code numbers which will tell you a range of resistance for that key. You can then buy the resistors that add up to your resistance required for that key, it is best if you test the actual resistor on the key rather than using online data, Once you have the resistors simply splice them with the two wires on the ignition switch. This fix will by pass the resistor on your key which is a very small security feature. You can now also make copies of your key withought having to pay special for a key with resistor in it. For this you would need a steering wheel puller, you can usually rent them from auto parts stores, or shops
Edited by: trofeo90