I have a 97 chevorlet blazer and when i go to start it up my blazer turns on and then randomly shut offs, but runs fine if i put it in drive.

Recently i have had my car jumped, and the previous owner put a hypertech power tuning module in it. I believe it has something to do with that. Am i right?, any other suggestions.

Any other symptoms?

Did you have the battery disconnected at all? Recently I had the battery in my blazer disconnected and then required a jump. Imeadiatly following that my Viper alarm system no longer worked. A voltage spike in the system fried the "brain" to the alarm. This could be the same type of issue with your Hypertech module. I would recommend removing the module and then running further diagnostics. If the problem persists then you know it isn't the module, if it goes away then you should contact Hypertech. They may have some sort of warranty program for damaged components. -Peace

Could be the Ignition switch.

Does your dash lights go out when the engine quits?
If yes, replace the switch.