i swaped my ecm to the 7747 so i could program chips for an engine swap im about to do. but my vats is still setting sometimes.
the ecm don't use the vats so i dont understand why it is still acting up. but forget it. does anybody know how to remove the VATS system.

tia,
RS

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1992 Camaro RS
Mods:
14x3 Open element w/ K&N filter, MSD 6a, MSD GM blaster Coil ,MSD 8.5 SC wires, AFPR,Fuel Pressure gauge(60Psi max), 3-Row Al rad. , 180* t-stat, Hooker 1 5/8 headers, 3" Catco cat, 3" Hooker Aero Chamber cat-back, "Ultimate TBI" mods

Best Time: 15.279@89.02MPH
Underdog Racing

 

I'm not sure which year & motors the 7747 ECM is used on, but the VATS enable function is controlled by a bit in the PROM. If the VATS bit is enabled, the ECM will not pulse the fuel injectors without a valid signal from the VATS module.

Tim

 

Underdog, since the 7747 doesn't have VATS, all you have to do is find the starter relay and jumper it.

OR

Visit the tech article page and do the bypass.

 

i have done the "bypass" but sometime it still sets, i think there has been a wire "repair" that has added resistance to the line and sometimes the vats gets mad, and sets =(

how do i jumper the starter relay??

TIA,
RS

 

What bypass have you done? Have you re-programmed your chip to delete the VATS info? The VATS will not pulse the injectors as well as not giving ground your starter enable relay, so it will take more than just jumpering your relay.

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1989 IROC-Z 5.7L

 

i have swaped the ecm to one that does not use vats(7747 ecm) i also have done the bypass that is in the tech articals.

thanks,
RS

 

I'd just either measure the resistance on the key. If you don't have the key then go to radio shack and buy that $5 roll of resistors and try them all. Then just wire it inline.

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, Jon (91 RS too many mods to list)