I have a Bonneville with a 1998 engine in it. Lately it has been stalling suddenly without reason. The check engine light comes on, the ABS light comes on (both stay on) and it just dies. Occasionally, it will restart after a few tries, but the ABS light remains on, and it will eventually die again within half an hour. It happens with a cold engine as well as hot. Sometimes if I notice the check engine light fast enough and floor the gas, it will not stall, but it doesn't work every time. Sometimes (if my husband is around) he will jiggle the wires going into the crank module it will restart again, only to stop a few minutes later.
Some of the suggestions were the wires (which we replaced), or dirt in the gas tank as it was low on gas the first few times it happened (but it happens when full too).
Can't afford to tow it to a garage to get scanned and repaired and can't trust it to drive it anywhere..
You can buy a scanner at the store for a fair price. There always good to have on hand with the newer computer controlled cars anyway. Good luck : ) if you get the codes come back and post them and we can help you further