The final piece of VATS is the Cranking Fuel Enable signal.
There are two ways to eliminate this last part. Either get a new ECM chip burned with VATS eliminated from the programming, or build your own “VATS Sim Chip” that will send the proper signal to the ECM.
For the purpose of simplicity sake, I would only recommend the ECM programming method.
When VATS has not detected anything wrong and is working properly, it will send a 5v 30Hz signal to the ECM to tell it to enable the fuel injection system during cranking. Once the the engine is running, it no longer needs this signal. If VATS has tripped or there is a problem somewhere in VATS, this signal is killed and therefore the ECM will not enable the fuel injection system to start the engine with.
Recommended Bypass Method: Reprogram the ECM
The easiest method is to get a new EPROM chip programmed by a reputable company. They can remove the need for the computer to check the VATS system at startup, thus eliminating nearly every probable VATS failure from keeping your car from starting. The company I originally used for this writeup and my own needs is no longer programming these chips. Contact me if you would like alternative vendors.
If you are one such vendor that would like to receive more business programming EPROMs, please contact me.
The process is not very expensive, relatively speaking, and can run anywhere from $100-150 depending what all you would like changed in the programming. While you are at it, give your vendor a list of mods you have done to the car so they can give you a nice tune. Even if you car is stock, ask them for a stock tune anyway, it will greatly improve performance, idle, and many other aspects of engine management.
There are two ways to eliminate this last part. Either get a new ECM chip burned with VATS eliminated from the programming, or build your own “VATS Sim Chip” that will send the proper signal to the ECM.
For the purpose of simplicity sake, I would only recommend the ECM programming method.
When VATS has not detected anything wrong and is working properly, it will send a 5v 30Hz signal to the ECM to tell it to enable the fuel injection system during cranking. Once the the engine is running, it no longer needs this signal. If VATS has tripped or there is a problem somewhere in VATS, this signal is killed and therefore the ECM will not enable the fuel injection system to start the engine with.
Recommended Bypass Method: Reprogram the ECM
The easiest method is to get a new EPROM chip programmed by a reputable company. They can remove the need for the computer to check the VATS system at startup, thus eliminating nearly every probable VATS failure from keeping your car from starting. The company I originally used for this writeup and my own needs is no longer programming these chips. Contact me if you would like alternative vendors.
If you are one such vendor that would like to receive more business programming EPROMs, please contact me.
The process is not very expensive, relatively speaking, and can run anywhere from $100-150 depending what all you would like changed in the programming. While you are at it, give your vendor a list of mods you have done to the car so they can give you a nice tune. Even if you car is stock, ask them for a stock tune anyway, it will greatly improve performance, idle, and many other aspects of engine management.