I have the stock alarm on my 97 z28. It worked perfect until recently. I often disarm the system/unlock and by the time I get in, It will go off. Does it about every other time i get in the car.

I can't think of any way to isolate the problem, does anyone have any ideas or what it could possibly be. Its is embarassing and annoying when your alarm goes off after you sit in it.

Only thing i can think off, A metal rivet broke on my window, so i haven't repaired that yet (Window can move side to side). Is it possible that when i jiggle the door or jump in, the window is hitting a sensor. But my question is, why would the alarm sound after i already turned it off.

 

I had a similar problem with an old POS Code Alarm alarm system I used to have back in '85. It tuned out to be a defective control box or "brain" for the alarm system. Got it replaced and the replacement did the same thing. That was the last time I bought a Code Alarm system.

 

I had the same problem with two different end results.
1. The first one was the sensor in the pass rear got wet inside the sensor and had to dry it out... then worked fine and alarm didnt go off anymore...
2. Trunk was not shutting properly so I had to adjust the trunk set screws.

Does the alarm turn off when you start the car?

 

That is strange - wouldn't hurt to try unplugging the shock sensor and see what happens.