Hi all, I am working on a 89 tbi 305, and almost ready to switch to carb'd because of my ecm/vats issues...I heard you can re program the prom to dissable vats...is there someone who can tell me how???or can help???
I've bi-passed everything vats dissables(starter, ign. coil) and the only thing I cant get is the injectors to pulse....I have spark at the plugs...fuel pump works fine...its just satisfing the ecm to give me pules to the injectors I lack.
I have a pass key module...and have a varable restor soldered in the key wires...and have adjusted it to all 15 resistences....but still no go. the security light just stays on with key on...

 

Disabling VATS via the prom requires a simple change to the "VATS" switch.

I recommend that you purchase the eprom burning equipment as you will need to make further changes to improve driveability and performance anyway. FYI, on a bone stock L98, I improved my performance by 30 HP at the top end and 30 lb.ft TQ throughout the mid-range to the top-end, plus I increased my fuel economy.

If you just by an eprom, you will not obtain those same results unless you get a tune done "hands-on". With a mail-order, they just tune it for "good enough", so consider you are leaving 30HP & 30TQ on the table.

Go to the DIY Prom Board and there are "stickies" on the top which tell you everything you want to know about eprom burning.

Good Luck.