I am buying a bank switcher soon and want to make a security chip for my $8D 730 that won’t allow the car to start. I have vats on my car but I also have a remote start alarm with a VATS bypass that could easily be used to start the car. I realize it’s not very likely that the car will would be stolen but it doesn’t hurt to take every step to stop it from happening.

If there a way to make the car not start without the ECM erroring out into limp home mode. For example could I set the injector constant to 0 or something.

 

Load one .bin with just FFs, that will put the engine into limp home mode.

 

Yeah, make the injector constant way off and that will make it either super lean or rich, never start...

 

I prefer a modest approach.
I have mine set for rev limiter at 1500 rpm and speed at 13 mph.
This way you don't foul plugs or make it undrivable.It happens accidentally when you forget to put the switcher back on.
It works good this way for me.. I just take off the switcher when having work done on the car by a shop or something so all they can do is move it around.
Saves all the hot doggin' for me!
If someone want to try to steal it, I can run faster than the car will go and if they punch it, it will die immediatly.
I really want to incorporate a run timer for some sort of anti-carjack thing as well. (more code...more code...)

 

I don't want the ecm to go ito limp home, then someone could steal the car.

 

I don't know what setting the injector constant to 0 would do. It might throw an error and end up in limp mode but you could change the frequency the VATS is looking for.
That would disable the injectors and give you no fuel to start.The ANHT indicates 33 to 66 hz.
Set them to 98 to 99 might do it.

BTW, I have a bolted on column lock and the above.
I hope it stays where I put it.

 

I misread what you said, I thought you wanted limp home mode.

I'd mess up the checksum in what ever you do, so the flashing SES light might clue them in, to it's not going anywhere.

If it will start and run at all, they might try idling it away to a waiting tow truck.

If I was doing a no run chip, I'd set the crank fuel to 0, and the MAP/MAF tables to 0. That way it won't even give a hint of trying to start. And verify that it won't try to start hot or cold.

 

With a bad checksum, won't the ecm go into limp?
(not to be redundant)

 

Ya, your right....

Think I'll just take a nap..

 

OK, just thought I missed something in the translation (again )

89 Iroc Z, if you try the injector constant at 0, let me (us) know if it throws an error. Would just be nice to know.
I won't be able to try it this week or I would just do it myself.
Thanks,
Jp

 

Having a switch to tell the ecm that it's in gear (or the clutch is out) is another way to stop somebody from starting the car. This way it won't even crank over, the key will just do nothing . It's even better when the switch is a hidden magnetic reed switch.

 

That is a good idea, I had one in my 78' regal 400sbc years ago.
I swapped in my motor and forgot about it until 4 hours of troubleshooting why it wouldn't start
I think the implementation of anything shouldn't cause you problems if indvertently triggered. Chances are you'll be the one to deal with it more than thieves. (hopefully)
IMHO a good visible column lock will stop the damage before the ignition and door locks have been poppped out with a screwdriver. Deterrents force the would-be to acknowledge that "this will take time and make noise" Even if they don't get the car, the damage left from an encounter is enough to make you want to kill someone.
I've had too much damage from idiots taking the stero out.
Sorry if I'm jacking on this one, just trying to help.
Jp

 

<---- haven't had locks on doors for 4 years, hasn't been broken in since . I use the alarm system to lock/unlock the doors and if the odd chance of a dead battery I can still use the key to open the rear hatch and climb in.
I also have a "stealth" stero system with a fake face plate. Only the kick panel speakers give them a clue, but they're idiots so I don't worry about it.
The in gear is a very easy modification, works rather well by disabling the starter relay.

 

On my Typhoon I just made a chip with the Rev Limiter at 500rpms. So it will just start and die. That way it won't even go into limp home mode and they will just think there is a problem with the Ty and give up.

 

In the Grand National crowd, anti-theft chips are really common. You have to perform a sequence with certain controls or else the car won't run. Is this what you are after?

You have a patch check a bit to see if its set, if not set the F/A ratio to zero, car stalls immediately after cranking. On the 148 ECM crank fuel is not controllable so the car actually starts and immediately turns off again.

 

Frankly, when I park my car for the winter, I pull the entire ECM out. It isn't going ANYWHERE then (without a tow truck). And just to make sure, I pull the rotor and turn the distributor. If I need to start it (I don't want it to sit too long without running during winter), I just adjust the distributor back, install the rotor, and hook up the ECM.

But, I have always thought about an "Eprom Virus" where the chip would go WOT on the thief after 5-10 minutes of running. (And start a tape laughing at the guy wishing them a pleasant journey to hell). Hell, it's halloween, what do you expect.

 

Sounds like a lot of work even though it isn't.
As for the Eprom virus, I've thought about it too. I think my most creative was one that locked the doors, rolled up the windows, and filled the cabin with nitrous.

 

Actually, that sounds more like a party than a deterrent. Dont you go to parties see the clownsmanning the large nitrous tank with balloons?

 

About 5 minutes. Longest time, is usually to find my key. I don't know how you have your ECM, but I haven't "bolted it in" for years. Even when I drive it, I just shove it up there and use some large sponges to hold it firmly in place. ECM drops out in seconds. I am constantly "tweaking" the eprom, always trying something new.

As for the dissy, I have a "alignment mark" to line it up for my 6* base. If I am just starting it, I don't even hooking up the EST wire. I only want to get it warmed up to the point the fans come on.

 

OMG stop!

 

Run a ground strap to the brake pedal,
Relay to dump the coil into the shifter handle

 

That'll wake you up in the morning.