Alarming problem....

You seem to infer the alarm is the cause but don't give any clues. Obtain and read the alarm documentation to excise it from the vehicle wiring. Go from there. Are you saying the battery is the car's original 1990 battery? In which case buy another. In trying to start, is starter speed normal? Are lights and fans operating normally? Smell of gas after repeated attempts? Stale gas in the tank?

 

There is likely a signal from the alarm that feeds into a relay. This relay blocks the ignition signal from the car key to the starter. Alarm electronics is messy by its nature. Unless you have a good schematic, or very knowledgegble about alarm, it is best to let some alarm guys deal with it.

Or, you can look under the dash, find the immobilizer relay, rip it out, splice the ignition wires back together, and start the car. Then, update to a new alarm.

 

Most good alarms will also have their own backup battery - hidden away. That way if the thieves pop the hood and disconnect the primary battery, the alarm will still work. In many cases if they also go for the secondary battery the system just goes into a "I've been stolen" mode and by default does not close the immobilizer circuit. With the secondary battery dead, the alarm may still not allow you to override the immobilizer circuit.

So you can go looking for that secondary or backup battery (small) and replace it or it may just be dead from sitting so long also. If its still a good battery, put a battery charger on your good battery and let it run a while. You may have to have your key in the run position to complete the charging system. If there is a secondary battery and its just dead, bringing it back to charge may reset your alarm.

Hope this helps,
Rick

 

paul
what does it mean when there is a smell of gas after repeated attempts to start the car?