alarm problem

Please help!
I have a 91 g20. when I bought it, it already had a factory security alarm and the after market alarm installed.

Now my car can't start. I tried to disconnect the after-market-alarm from the car. I still can't start the car.

I'm pretty much sure it is the alarm problem.

would someone please tell what wrong and how to make my car start the engine. I don't care about the alarm. I just want to have my car running.

Thanks,
David

when you start the car, or crank it over i mean, does the engine light come on? if so, this could be two things, check your fuel pump fuse or maybe check your key. European nissans have a transponder built into the car key. If yours has one, it will be just above where the actual key is moulded onto the plastic and is shown by a red rectangle about 4mmx6mm. You can remove it with a small pin, but gently pull it out to reveal a small glass tube (transponder) This could be broken and immobilising your car.

Your response had added to my learning knowlege. I apreciate that.

After spending days and nights thinking of what kinds of the problem is or are, I decided to take to the dealer. The Infiniti dealer did the check on my car. Then he told me the starter is bad. He also told me it would cost me $450 to fix it if I leave it at his shop.

I decided to take home and replace the starter by myself. My car is working now.