david roush

iTrader: (1)

Just trying to finish up a tuned port project. Trying to figure it all out......VATS MODULE : What is it's primary function and where can i find it ???? Any help ????

Jza

Damn David, you still working on that?!

The VATS module is simply put, a device that reads the resistor "chip" in your key, determines if it's the "correct" one for the car, and tells the ECM that it's "allowed" to start the car.

You can find it tucked up inside the dash somewhat close to the ECM itself. Follow a dark blue wire that goes off on it's own from the ECM to a box way out there somewhere. It should also have several wires (couple yellows, a black, a red, and some others I'm not thinking of right now).

Don't give up on it and just rip it out like most people do. You'll be glad when you get it all working and STILL have the VATS functional. Not to mention proud.

david roush

iTrader: (1)

damn is right JZA. Actually i had to redo the harness (alot). And everything functions properly on my friends scanner, the vats has been the only thing holding me up, well that and time to work on it. Originally i thought the vats was only controlled in the ECM and just recently found out there was another module i was missing. At least that explains why i didn't have any power to the fuel pump relay and it kept on reading "vats fail" now all i have to do is go back to the donor car and locate it... Thanks for the info JZA :hail: :hail: :hail: this has been driving me nuts for 3 months now

david roush

iTrader: (1)

I went back to the donor car and pulled out what appeared to be the vats module from under the passenger side underneath the dash. Took it to the dealership to run the part numbers and as it turns out, got the wrong part. Got the cruise control module. Back to the donor car again i suppose. But i did find out from the dealership it is on the drivers side of the car. Maybe someday i'll get this right, but i doubt it.

joker37

VATS Module is gray... and has the words PASS-Key written on the sticker. On the 89 Trans-Am doner car i have it was above the radio, but behind the gauge cluster. Its a pain in the behind to get out, but it was done that way in order to give it a bit more security. It was just right of the buzzer in this car... where as the ecu is on the passenger side. The ESCM (electro spark control module) is a yello box closer to the computer, just to let you know that isn't it if you come across it.

Hope that helps, if just a little.

Joker

david roush

iTrader: (1)

Thanks joker but now someone has told me the vats module has nothing to do with the chip's value in the key blank so looks like i need to set and rethink this over again. Probably just gonna send the ecm out and have it reprogramed. It's alot cheaper than having a chip burnt. Damn VATS !!

joker37

what did that person tell you?

The vats module is what checks the value of the key's resistor pellet. When they put the module in the car (like brand new) the module sets it self to the first key reistance put in the lock, and that is the module's reistance forever.

The only way to get around it is to ground the starter rely at the appropriate wire, and make something to send a square wave pulse to the ECM to enable the fuel injectors.

OR

Burn a new prom with Vats disabled.

The new prom tells the ECM to ignore the pulse and just enable the fuel injectors. The new chip would just cost $150 bucks... and the last time i priced a new vats module it was .... $150 bucks. Your choice. And you can't have the ECM reprogramed... just the chip that holds the individual car's value.

Personally... i want the chip, and i think i'll make my own anti-theft system... like a switch to cut the power off at the TPS sensor... stupid thing would kill the starting ablity.

Hope that helps... if you have any more questions let me know.

Joker

2vmodular

are only 15 resistor values used on vats key blanks. can cycle through the various values until you get the proper one. when you get it, the fuel enable signal will start pulsing.

alternatively, can build a simple 555 timer circuit to generate the required square wave. see this thread for more details:

https://www.thirdgen.org/techbb2/sho...hreadid=118472

david roush

iTrader: (1)

well for some reason after i put the tuned port on my scanner kept reading "vats fail"......Can't figure out why. I have an interrogator and couldn't get it started with trying all 15 values. And where are you getting a chip burned for $150 ?.. Hypertech wanted $400 , fastchips $350 . Priced a vats module at the dealership and it was $200.

joker37

Price for a no-vats eprom is $150. Give us a call if we can assist you.

Vince Flores
Fuel Injection Specialties
210/654-0774

email: "Fuel Injection Specialties"
fuelinjection@fuelinjection.com

---------------------------------------------------------------------------------

I looked this up and sent these guys an email about getting vats removed from my car. This was their reply.

Joker

david roush

iTrader: (1)

cool....thanks for the leg work joker, much appreciated !!

89formula#1

i have grounded my starter and ripped out my computer caus ei switched to carb from tbi. do i still ned this ship in my key?? also can i take it out without messin it up and get it back in???