[Charge]

Hello,
I'm writing on behalf of my father's 1995 Bonneville SE(3800 NA). A while back, the car started stalling intermittently. Basically it'd lose power while driving and usually catch and immediately restart(almost stuttering...but it did completely go out). Sometimes we noticed the voltage gauge sweeping just before this would happen.

Took it to a mechanic. They replaced alternator and checked wiring. Battery was only a little over a year old and tested fine. They were not able to reproduce the problem. It occurred again, took it back. They eventually replaced the cam position sensor. Still occured intermittently(about 3-4 times a week). Car has spark and basic wiring was checked.

Now, we noticed that sometimes, when you open the door, the door chime goes off, when the key's not even in the ignition.

It's been suggested that it might be the ECM...but that's a rather expensive part. My dad already purchased a new car to replace this, but we'd like to get it running to sell off. Any ideas?