i have a 91 Z and i believe the vats went bad tonight, i threw on my code reader and it came up as a code 46(VATS) i also have a 96 camaro parts car and if electronically i can change the one of the 96 into my 91 then ill start with that. if i cant switch them around then im going to do the bypass if this ends up being the problem. im not sure if my 91 has a security light or not but if it does then it didnt turn the light on. any help asap would be greatly appreciated

 

I would plan on doing the full bypass. Chances are that the ignition key from the 96 is the wrong resistance and would not work with the 91 vats module even if the ignition cylinder is interchangeable. I priced one before and the 91 cylinder is not very expensive but can be troublesome to swap.
I would buy a bypass module and bypass the starter relay if that is your intention. I would also reccomend you stay away from the cheap cheap bypasses on Ebay. I tried two different ones to no avail.

 

what makes changing the cylinder hard? ive done many in the past on older stuff and havent had any trouble i know its a little tedious but i dont mind. if i get a new one will it have to be so to say the same ohms?

 

If the ignition cylinder is the problem it is because the little wire broke somewhere. The ignition cylinder does not have anything to do with the resistance of the key. It only has the contacts to allow a small current to go through the resistor in the key. When you replace the ignition cylinder the new key will need to have the same resistor chip in it as your original key.
Though not likely the problem have you tried cleaning the visible areas of the resistor chip in the key. If that area gets to dirty the restistance will increase and read to high causing a VATS problem.