I have an 86 Trans Am with a TPI 305 that I am swaping an 89 350 TPI into. The 89 parts car has a VAT system. I know the cars have the same ECM but have to put the 350 prom over to the 86 that doesn't have the VAT system. Is the programing in the prom or computer and how can it get around it to be able to start the engine? No carb answers please I'm keeping the TPI. I've tried looking it up but either ain't asking the right questions or just not finding the answer I'm looking for. Thanks

 

It's in the chip. It'll look for the VATS signal, and if it's not there, no go. The easiest way around it would be to have a chip burned with VATS disabled. Next easiest, you can buy a module that generates the VATS signal and wire it in, or use the VATS module from your parts car and wire a resistor that matches the key value, to the module so it thinks the right key is connected.

 

if you want it programmed out send me a pm, there might be a fan switch change between the two memcals as well if you have ac. Most 89 f body’s are normally open pressure switch while older years are no this causes the fan to come on with the key on unless it’s reprogrammed accordingly on the ac pressure switch is swapped from your donor car.
https://m.ebay.com/itm/DFVATS-Bypass...%257Ciid%253A4