1999 Integra, 75k
My Kenwood car radio, remote … was stolen, while parked in the mall parking structure. No sign of breaking in. No damage whatsoever. Dash kit also stolen. Went through the boot but didn’t take any.
I am considering a car alarm (without engine immobilizer - since it may give trouble later on).
Would such car alarm, prevented such a theft? People tell me if someone opens my car w/o the remote, it would have alarmed.
Would it be a good idea to install an alarm while I install a new car radio?
Gaining entry to a locked vehicle without damaging anything is easy to do, even for an amateur. A car alarm will help prevent many of these such occurrences as most thieves would rather not deal with the screeching and beeping and the attention it could draw. A professional thief will take the whole car, regardless of whether it’s locked, has an alarm, etc. I would also suggest that you have a kill switch installed for the alarm, hidden where you can use it readily, in case something goes wrong with it and you need to shut it off.
I found it to be a good investment. But then I got a 2-way paging alarm that will tell me when the alarm sounds. A straight alarm doesn’t do much good because everyone ignores them since they’re always going off accidentally. It’s better if you can run out and catch them in the act - -obviously, don’t do anything stupid and get shot.
Would it have prevented the break in? Probably not. But it might have prevented them from taking the time to steal stuff.
In other words, you got lucky this time because they used a slim jim to get into your car. If they’d done a smash and grab, then your window would still be broken even if the alarm sounded.
Best first-line security is a detachable-face plate radio (and take it WITH you, don’t toss it in the glove box. If they don’t think there’s anything worth stealing, they’ll move on to the next car.
As for alarms, even with starter kill and all the bells and whistles, a really determined thief will get your stuff and/or your car.
What I did on one of my cars was to get a Compustar 2 way paging alarm. It has starter kill (don’t worry about future problems. If you get a competent alarm installer you won’t have them, and if there’s an internal problem, Compustars have a lifetime warranty) I then added a hidden backup battery, and I added a second 130db siren inside the car behind the dash. This way they can’t just pop the hood and disconnect the battery to kill the alarm, and if they want to steal my radio their ears are gonna bleed from the siren going off inside.
Whichever alarm you get, do NOT let the installer install the little flashing LED that comes with the alarm. Why? Because each alarm has a different one, and each alarm has a kill-switch routine built in. An experienced thief just has to look at what kind of LED you have, and then run the kill switch sequence to shut off the alarm. I had my installer put in an LED that looks like the one that comes with another brand of alarm. That way they’ll run the wrong sequence and waste time trying to shut the alarm off when they could be stealing stuff 
You mean, kill switch to shut off the alarm?
Just about all alarms have a built in kill switch. No need to install a separate one.