Cascade Crew

[91camaro_rs]

what is the easiest way to bypass VATS? how do i know how much resistance to use if i dont know what the number was for the orignial key, for that computer

[Schultzy89GTA]

If you have the original key you can measure the resistance and put the appropriate resistor inline.

http://tpiparts.net/vehicle_anti_theft_system__vats_/

-Schultzy

[91camaro_rs]

original key as in the key that went to the ECM that i put in my car?

i only have the key that went to the v6 that i pulled out, too bad that computer wouldnt work

i did notice that the computer from the v6 also ended in 730 like the v8 one, could i use the v6 computer with the v8 chip?? would that even bypass VATS?

[Al Hasse]

The ECM doesn't care what value resistance the key has. What matters is that the key resistance matches the VATS module, which is where you would bypass it with the appropriate value resistor(s).

When the right value is read by the VATS module, it sends a signal to the ECM.

[91camaro_rs]

so do i even need to bypass it then, considering i didnt do anything to the VATS module and i have the keys for my car, is it just something else not making it start?

[Al Hasse]

What does it do? Does the fuel pump prime when you turn the key? If it does, chances are it's not VATS.

[91camaro_rs]

when i turn the key all it does is the lights and guages turn on, thats about it, i cant hear the fuel pump or anything

[Al Hasse]

It might be worth a try to bypass the module. It seems to be a common problem for the wires in the ignition lock cylinder to break, then VATS keeps the car from starting.

I haven't done it before, so I couldn't tell you where it is other than under the driver side dash. Find a resistor or group of resistors that total the resistance of your key pellet and install per the following link.

http://vats.likeabigdog.com/

[Alphius]

Do you have a blinky security light when you try to start the car? Does it crank and not fire, or does it not even crank at all?

Your original VATS module is still there and connected to the ECU, so your original key should still work fine. Other people here are more VATS experts than me, but if I was you I would check for fuel pump prime by having someone listen at the bottom of the tank and check for spark as well. I'd only suspect VATS if I knew for sure that the symptoms of no-start matched what VATS does when it locks down the car. I do not know what VATS does to prevent start, but I'm sure someone else here does.

If it helps (probly not) the V8 ECU is from a '91 as is the V6 ECU.

[91camaro_rs]

security light does blink when i turn the key, but nothing else happens other than the guages move a little, i cant hear the fuel pump and the motor doesnt even crank...

could i have a bad ground? maybe i wired it completely wrong, cause idk how it SHOULD be wired.

[Alphius]

[Schultzy89GTA]

[91RSVert]

The vats light does light up for a second when you start the car even if its working.

As Alphius said. The vats mod was what was in your car before the re-wire, then it still matches your car and is fine aslong as you hooked up the ecm correctly. All of that should have been simple plugs... But I would check that circuit over again. Maybe have changed what position it was in the plug between years????

When vats acts up, the car will not even crank... I dont remember about the fuel pump. It takes 5min to "reset". I have had it act up before and get it to work after warming the key up. Try blowing out your ignition switch also.

Make sure you have the purple wire on the correct side of the starter. (my selonid has 2 little lugs, plus the big one)

Double check grounds, I have missed the ones on the back of the heads, and the intake several times Also dont know if you dx'd the battery ground to block, but check it also.

[91camaro_rs]

i have no idea where which ground is supposed to go...i know my battery was grounded to the frame when i had the v6. the VATS isnt in the wiring harness at all is it?

i dont know where the vats thing is but im pretty sure i didnt mess with it

[91RSVert]

My battery ground goes to my block, on both the v6 and v8. Then you should have a ground strap from the back of the block to the firewall(head or bellhousing). Also a short small pigtal from the battery lug, to the body.

The vats module itself is somewhere way deep in the dash, but it connects to the ecm via one of the quick connects under the pass side of the dash. Then has a short run to the ecm itself. So more then likely, you played with the wiring. IIRC its a blue wire.

I didnt follow your orginal swap that well. I assume your car is a 91, what year harness/ecm did you drop in?

:edit: I can help you a little more in about an hour after I get home and can pull my dash panel n snap pics if you need

[91camaro_rs]

if you could take pics that would be awesome, cause i am so lost at this point

so as of now i have my positive battery cable running to the starter and the little cable that is connected grounds at the body

im not sure where i should have the negative battery cable ground at

only thing i have plugged into the alternators little post is the wiring for the fuel pump

i dont even know where the ground is supposed to go to the starter...i made a wire and connected it to the frame...

and i do have a ground strap going from the firewall to the block

i took a carbed 305 from an 85 Z28, put a 86? T/A TPI unit on it, computer came out of a 91 and wiring came out of a GTA not sure on year, he said he was gonna use it for a LSx project

[Alphius]

[91RSVert]

ok, were getting you confused.

First, which ECM are you using since you were given 2?

Grounds. You will have a bunch of little hoops within the harness, all need to be grounded somewhere, aslong as its steel. As far as I'm concerned, your battery cable needs to be to the block. But if you have a good solid strap to the motor, should be good as you have it(I doubt you messed with it anyway).

Pos. The big one should be to the starter as you said. With it, should be some orange and red wires that have little white "fuses" that go to the harness. All should be on the big lug.

Starter. Your purple wire should be on a lug all by itself. My starter has 2, and I had it on the wrong one at first.

Alt, you have the plug. Then you have a fat red wire, iirc, it should feed down to the starter???

Fixing to go snap some pics for you. But my harness will be different since its a 2002 harness.

[Alphius]

Listen to 91RSVert, he's more succinct than me. All his wiring advice there is accurate. He posted while I was writing mine. But I got the VATS diagram, so if that's the problem it's in my post. VATS being screwed up will make the security light blink multiple times.

[Schultzy89GTA]

gracias