i have a 91 firebird 305tbi how can i disable the VATS?

The best option is to buy or burn a PROM with it disabled. You can buy a VATS bypass module from Baker Electronix (or make your own) but the one I bought from Baker didn't work. Once I got a PROM without VATS (from an 87 car) it fired right up!

Save yourself the hastle and have someone disable it in your PROM for you.

how do i disablbe it in the PROM

You have to have the bruning equipment and software on your computer (home PC). Someone might be able to do it for you. Go into the DFI and ECM forum and see if there is someone in there OFFERING this service.

I'm not saying that Baker's module won't work for you, but it sure didn't for me. I'm sure they work but for some reason it didn't work on my car. I think it was broken. They still haven't diagnosed the problem.

One of their modules is easy to hook up, and it may work for you. You will have to get the $30 DFVATS module. Make sure you know exactly what you are getting and ask all the questions you have before you buy.

I still say get it disabled form your PROM if someone wlll hook you up.

Easiest, cheapest way.
Find the resistance of the pellet resistance of your key and match it with one in the chart. Then go to radioshack and find a resistor between the minimum and maximum resistance of your key.

Doing the resistor mod doesn't actually disable VATS, that can only be done with a custom PROM. The resistor thing does however bypass the key-reader in the ignition, which is the most common failure source. It essentially tricks the VATS system into always thinking the correct key resistance is there. I did this mod after my key-reader broke, and left me stranded at a gas station.

that is so kool,
im keeping this site.

how do i figure out what key i have

What about the key reader broke? I've been helping a friend with a no start problem on his '91 RS and after a new starter and new ignition switch (down beneath the dash) it still wouldn't start with the key. I located the starter enable relay and was able to get the car to crank when I popped the cover off and held the contacts together. I'm going to order a new relay Monday morning but at this point I want to be sure all the bases are covered.

this is a very common problem on the older cars. and very excelent explianation JTNKTZ

If you find the right code. This might help

http://www.ecklerscamaro.com/product...dept%5Fid=1620

You have to measure it with an ohm meter. My key is #3.

This is a very good post. I had this problem last Nov while traveling. Had to have the car towed to the nearest dealer....$350 later, VATS was fixed and I was back on the road...now the problem is back

I've figured out I have key 13 and have ordered the bypass from Hecklers....I looked for a resistor from Radio Shack, but they did not have one in the range of 7.2K-7.8K. I'll post up how it goes once I receive the by-pass.

It's not easy to buy the exact size resistor, that's on purpose, so that thieves can't do the same.
However, you can buy two resistors and combine them. Let's say a 6.8k and 680. Wires in series, that gives you almost 7.5k, which is in range.
That goes for other values. A simple combination of two easily available resistors can replace any key pellet.

However, it's not a fix, it's a hack. After this modification, any idiot with a screwdriver can start your car and drive away. Just to let you know.

Hope this helps.
Lou

Shouldn't you cut the wires that run up to your key switch when you put the resistor(s) into the plug, or did you just unplug it??

Reason I ask is that my VATS works fine most of the time, but every once in a while it will not read properly and of course the car refuses to start. If you put the resistors in and then your key is inserted, then the resistance that the car actually sees would be out of range. I am going to do the 'resistor in the line' mod soon, but want to make sure that I do it right. I also don't plan on getting another key or anything like that.

Just unplug it. If your key reader completely failed it wouldn't matter.

Yep, I do a lot of out of town shows and really don't need it to fail while I'm on the road...thats already happend once. That said, I reconize it's not the optimal fix but a fix none the less. I use a club and a brake lock on both my TA's. If bad guys wan't either of my TA's bad enough to defeat those two devices then the VAT's is not going to stop them.

Just unplug the VATS and the car will start....really?? or do I misunderstand what you are saying? If true, then any thief in the know would just unplug it and go from there. I'm doing the Mothers Day thing today, but next week I'll give it a try when I receive my bypass from Hecklers Camaro.

I beleive the unplugging recommendation was in response to the question whether to cut the wires to the ignition cylinder. I don't think ACCLR8N meant to unplug the whole system. That would not help you start the car, as you correctly stated.

Lou

Why not do something similar to the resistor mod for the IAT? Find the correct resistor/s and figure some way to securely connect them to the connector leading to the VATS module like a plug in module of sorts. This way you avoid cutting the wiring and if you ever decide to sell the car or whatever else it's easy to reverse.

Yup, that's a good idea and it's what many of us do. However, it's not always easy to find the right connector and not everybody is worried about reverting things back to stock so cutting and splicing is an easy option too. I'm not saying I suggest it, just that it's another option that others use.
There are usually many ways to fix things on our cars and it's ultimately the owner's decision.

Lou

why do that at all?
it makes the car easy to steal.
if you do have a vats problem it will not fix it by constantly feeding the code into the column.
if you had a bad cylinder would you just pull the plug wire to it and then the one on the other side to keep it in balance? no you would fix it.
some problems just need to be fixed and a vats problem is one of them.

My suggestion was not intended to be a permanent fix, but a temporary one for in the situation of JWKbride. IF VATS was the cause then in roughly 10 minutes you could be back on the road and you could make the proper repairs when you got back home.

Well, no matter if you by pass or fix the VATS this is a good thread for options. I would like to see someone post an equally informative thread on how to fix the VATS vs Bypass...then you could really weigh your options.

In my case, I have a club and brake lock that goes everywhere with me and gets locked when I'm out of the car...so VAT's is not a critical to me.

That said, 2 years ago, I did have a friend who's show winning 3rd Gen was broken into at the hotel in Dayton, OH the night after the TA Nationals. The thiefs broke the steering column and tried to take the car, but the VATS would not allow the car to start....this is the only thing that saved his car from being taken. Two other vehicles in the same lot were not as lucky.

I received the bypass from Hecklers late last week (it was on back order). I found the wire as depicted in the picture above (orange wire) in about 30 seconds. Unplugged it and plugged in the bypass and "Whaala" it started.

The whole bypass took all of 5 mins or less and cost $25+$10 s/h....best $35 I have spent in a long time. I know it defeats the security feature on the car, so if you like your car I would also invest in another form of security such as a Club or Brake Lock....(I use both) if youby-pass your VATS.

Anyway...great thread and thanks for the opinions and direction.

this site was right on the money. Breaks it down scooby doo style for you. Gotta be pretty dumb not to know how to do this

http://www.youtube.com/watch?v=AKfn7J9CeZM&feature=fvw

hey i tried it and my meter read 2.35, so i assumed 2,350 ohms right. Well i made a resistor for that value and tried it and it didn't work. What is the deal with that?

Or you could just switch to an aftermarket EFI system like Megasquirt, gain full real time tuning and flex fuel capability, datalogging, autotuning, keep your stock harness, and make performance parts changes incredibly easy. All for under $500 for MS-III ($350 for MS-I).

After replacing my third vats ignition switch I got frustrated with it so I soldered my spare key to a hidden toggle switch and unplugged it under the dash and soldered it to it. Now I flip the switch when I park it so it is still functional

You can always take the resistors out when you leave the car. My dads 91 f-150 truck had a key fob type thing under the dash that when removed didnt allow the truck to start. Wire in the correct resistors to the vats system so they are removable and its essentially the same as the resistor in key set up from the factory (as long as you take the resistors when you exit the vehicle". I did that before I did my engine swap and lost the ECM altogether.

what if i have an 1986 trans-am and might buy a 1988 350tpi vette motor or a 1989 trans-am gta motor both come with ecm and prety shure both have the vats how would u run these motors that were designed with vats and run on my 1986 trans-am

You would either need to have the VATS programmed out of the ECM, or get the bypass box.

ur talking about the bypass box from hawksthirdgenparts

you can but it from there, but yes thats the one.

how or where would i hook up the vats bypass key from hawksthirdgenparts in the description of that part it saiys power ground and signal where would i hook that up to my 1986 ignition or would it go near the computer

The ground can go to any ground source. The power wire gets a 12v switched, thats only on when the key is on. The signal wire gets wired into the VATS signal wire on the ECM connector. Youll need to look up a pinout for your ECM connector to find which wire that signal wire is. Its usually a dark blue I think. It should be the only VATS anything wire labeled on the pinout.

i have a pic of the connector to ecm pin do u know which one it is here is a pic

traviz401 and vettoz can u elaborate or be more specific on where would u hook up the wires on a vats delete box i can read the wiring diagram on vettoz but not to good on it like if u can send pics of where i would have to wire the 12v, ecm vats signal wire im sorry im not to smart when it comes to hooking up wires

if you look on the pic you posted, the top plug, pin b6 is labeled as vats...thats the wire you need to splice the signal wire from the bypass box into. its labled as a ppl (purple) wire

oh o k i think i can start to see the picture ground basically anywhere there is ground signal gets spliced to the vats purple wire and the 12 volt gets spliced on the hot on the ingniton right

exactly

thanks travis401 ur a great help and thanks to vetteoz

Hey ... I found this connector and it stubbornly refuses to come apart. Is there a trick to this one? A locking tab or something I am not seeing? Thanks.

The connector under the dash for wiring in the resistors for the bypass? Yes it has a clip on one side that needs to be pushed up while pulling the plugs apart.

Thanks ... I did that .... it was just being extra stubborn. Brute force carefully applied with the clip gently pried up eventually did the trick.

Thanks again!

I'm having trouble seeing how this would work. The resistor is not in series with the circuit, meaning there would be a different value read by the VATS - assuming that our keys are in series with the VATS circuit when they are in the ignition cylinder - unless you unplugged the connectors and put it into the back of the connector that runs to the VATS module.

http://www.youtube.com/watch?v=AKfn7J9CeZM

Yes, in this video he has the resistors in series. Great vid.

All this resistor nonsense.....

Behind your drivers side kick panel there is relay with 4 wires going to it. I Un mounted the relay, pulled the black plastic cover off of the top of the relay to expose the contacts. Now here I simply wrapped the lever with electrical tape so that it is always in contact with it's contact point. This will give the signal to your computer that says you have the correct key inserted and your car will crank everytime. Hope this helps!
-Sean

That relay is the start enable relay, not the vats module. Its part of the vats system, but doesnt send any sort of signal to the ECM. Sounds like your vats was partially bypassed to begin with.