95 caprice dies after remote start

1.) Did it happen the same day the remote start was installed?

2.) Who installed the remote start(shop or boyfriend)?

3.) Did the car have any problems prior to the installation or any work done?

A friend that owns a shop installed it, he came out and disconnected it, to see if it continues, but he only disconnected the hot wire, all the stuff he spliced into is still spliced.  after he disconnected the power to the alarm the horn would blow everytime i hit the lock/unlock switch for the doors. (that was the day before yesterday. After he unhooked it, he was on his way out of town. but this morning i had the same issues, I had the battery and alternator checked, they turned out good.  The only prolem i had before the install was the check engine light was on but no symptoms, no-one can check it for me because it is a 95. I want to buy my own scanner but i want it to read obd1 and obd 2 (any recommendations on this?) I was looking at the autoxray 2500.

Anyway even though the engine light was on weeks before, i did not have any problems until right after the install.

thanks