[BackinBlack]

If you want to disable or remove your OnStar box:

All the brains related to the OnStar operations are housed in a single unit. The GPS processor is there, the system microprocessor is there, and the CDMA modem is there. Get rid of this box and you get rid of Onstar.

Of course you will lose lots of other features in the process but, hey, your paranoia does not come without sacrifice, right? Also do not tell your insurance company you did this because they will remove some of the discounts you get for simply having the Onstar safety and anti-theft functionality in the car.

For those interested:
Anything the OnStar unit does (unlock doors, send Navigation directions, disable ignition, detect airbags being deployed) it does by way of the proprietary Control Area Network or CAN bus. All the electronics modules in the car can talk to each other if they are on this bus (not all modules are). So the Onstar box sends some communication on this bus that the PTC recognizes are for intended for it, and there is probably some code in the PTC that executes the ignition kill once it receives that message. If the code was written to do it (maybe it is, maybe it isn't, I don't know), they could shut off the engine literally anytime.

A theory as to why they do it the way they do:
What happens in the middle of a high speed chase where the Camaro suddenly is commanded by Onstar (who can be commanded by the authorites) to kill the engine and it loses Power Steering and Power Brakes? A crash. If people get hurt you have a lawsuit on the city/state and on OnStar. So this is likely why they do this 10% throttle or 'next time the ignition is turned off' intervention. Its a smarter, safer solution to the problem of a speeding car thief or evading criminal.

I happen to love the Onstar functionality and can tell you that beginning in MY2010 many Chryslers will have a similar capability, called the PASS, and within a few years all Chryslers will have it.

Ford is expanding SYNC to be closer to what Onstar is, although they are implementing the features differently.

Import car manufacturers are bringing the same tech into their vehicles as well.

The point being if you are afraid of this technology & plan on buying a new car in the next few years you will have to deal with it.