vl5150

I just did this on my 1990 and the documentation here didn't really cover the year really well so here it is. You need to handle VATS fuel interruption and starter interruption.

Fuel:
You can get one of the regular VAT bypass boxes here: http://www.bakerelectronix.com

I also disabled VATS in the bin file.

The blue wire goes into the wiring harness under the hood where the computer is. Looks for the blue on Red and number 6. I already built 12v switched capability into the car using the no longer used CAGS relay wiring (pink/bl stripe) and sending that into a fuse block. That box handles the VATS fuel problem.

Starter:
You're 1/2 way done. There's a VATS starter relay that needs to be disabled (or more correctly bypassed). It's located behind that carpeted area under the steering wheel and above the pedals. Remove the carpet cover, then remove the metal cover beneath it. My service manual was incorrect on the location of the relays so look for the relay with the 3 thick yellow wires and one thin one. Remove the relay, cut the yellow/black stripe at 12:00 and the yellow at 9:00 (looking from the steering wheel)

I soldered these together and the car starts now with the regular key I had cut at pepboys.

Button it up and you're done. One less mechanical relay to leave you stranded.

UNCLEBILL

Thanks for the info... I also have a1990 Vert and will save all info on 1990 related.
Bill

MrWillys

I think it would have been much easier to just disable it in the programming. Then bypass, or just ground the yellow wire coming from the CCM to the starter enable relay. Done

You can also disable CAGS in the programming.

vl5150

My bin was set to disable VATS and the car still didn't start with the new key. I searched and searched unsuccessfully for the exact tune changes or for specifics to to disable the VATS by bypassing the starter relay. So I took matters into my own hands and found my own method with no electrical skill. Hopefully others with a 1990 will be able to reference this and save some time.

aklim

I'm curious. How problematic is the VATS system that it needs to be removed? My 91 F body was running till 04 when someone got it totaled. My current Vette is also a 91 and hasn't had that issue.

So how much trouble does the thing cause? Seems like cutting the ***** off a girls so she doesn't get cancer there. Might make sense if she is very high risk so how much VATS failures do we have?

vetteoz

Didn't start or didn't crank ; two completely different problems

Using a enable signal generator as you have done is well documented as a solution to VATS problems
on the CCM equipped '90+ cars

Loopidoo

My vats failed,(stranded twice) I did not research into it, to see if it was the key or ignition switch, so off to radio shack, got some resistors and matched the key, soldered together and plugged in. BAM no problem. 10 bucks and good to go. They get dirty and fail. These are old cars, low mileage or not.

Cliff Harris

My VATS system kicked in several times, completely at random and years apart. It finally got pretty bad when I couldn't start my car at an autocross and people were yelling at me to move my car up in the staging lanes.

The early VATS cars had a problem with contacts in the ignition switch. The original contacts would get corroded and not make a good connection. There was a recall on this and I ignored it because I didn't have the problem very often. After the above autocross incident I bought the kit (new ignition cylinder and keys) and I have never had a problem since then (I did this around 1995). The new keys were a tiny bit longer than the original keys. I guess that's a way for the dealers to tell that the modification has been done.

A side note: when I took my old ignition cylinder out one of the key pellet contacts was bent in a U shape.

hooked073

30yrs of experience tells me this systems are pretty reliable. Vats is blamed for a lot of things that are not vats related. personaly I would repair what is broke rather then tear it apart

vetteoz

Like many other items on these cars , nobody ever does any cleaning or preventive maintenance until it fails ;
then they complain saying what a POS it is because it only took 25 years of abuse

Bandit1977

As a newby to C4's, what sort of maintenance and/or cleaning are you supposed to do?
I've got a 88 Vette with 45k miles on it, every time I drive it I wonder if the dreaded VATS problem is going to rear it's ugly head and leave me stranded somewhere.
If there's some sort of preventative maintenance I can do I'd like to know what it is.
Thanks,
Ken D

vl5150

To answer the question above, without the starter bypass, the car didn't crank and the security light came on. The Baker unit did not work as a standalone product. So I'm in a situation yesterday where I cut into the harness with nothing to show for it.

Why I disabled VATS:
1. I wanted to because I didn't like it.
2. The system uses a mechanical relay that can fail.
3. The system uses a mechanically sensed resistor on the key that can fail if the contacts get worn.
4. I wanted to use a regular key without a pellet.
5. I garage keep my car.
6. I had a taste of VATS in action when my key failed and felt very exposed in a dangerous parking lot.

To answer the question on preventative maintenance, I'd say the main point of failure has to be the relay. It would have the same failure rate as the other relays on the car. In this case a 23 year old relay that is worth less than $1 can disable the entire car and can potentially leave you in a dangerous situation. No thanks. I want to control the car, not have it control me.

So once again here's the instructions that I found lacking on the forum for reference, with no intent on drawing a debate. The merits of doing so is a personal decision and has been discussed here for many years.. If you want to remove VATS then do it. If not, then don't. It's your car.

vetteoz

Something was wrong.
With the starter relay bypassed , VATS has no influence on the starter operation



Which is why it is commonly recommended to bypass / delete the enable relay completely.
VATS will still prevent the car from being stolen by disabling the injectors

The starter relay is largely ineffective anyway.
Any thief with enough time can easily run a wire from the batt to the starter solenoid to jump the starter.
Only the fuel cutoff is effective as a anti theft measure

vetteoz

Clean the contacts in the Ign barrel that get clogged with debris preventing the key from being read correctly
and buy a new key with correct resistor pellet before yours wears out and leaves you stranded.

Bypass the starter relay as noted above to remove a potential fail point

MrWillys

I think of VATS like this. My Jeep used to get hot and the wires to the starter would see a voltage drop and not allow it to start. Having a screw driver in your glove box for a key is not good. GM new this was a problem, and some big block C2's came with Ford solenoids. When my wife and daughter got stuck in the Jack in the Box drive through that was it. I converted to the ford system and haven't had a problem since.

VATS is the same thing for me. One failure and it's not worth any false sense of security that may be perceived. If a thief wants your car he knows the work around, because the system has been out for so long. Just my 2 cents!

WVZR-1

No - not in production. The remote solenoids were added 1st by motor home chassis converters whose product had higher engine compartment temperatures than most. The remote solenoids on any passenger car was that of the owner or an add on by the builder. I don't even believe the Yenko product had that feature "as built"! Does it correct a "hot crank"? In most instances.

The analogy I don't think is appropriate either and the elimination of is a decision the owner needs to make. It can certainly create "havoc" for diagnostics and trouble-shooting for the next guy OR maybe yourself.

Your "Jack in the Box" experience was "self induced" - maybe just a learning experience. Your fix was appropriate but maybe just a little late, knowing you had the issue!

aklim

I'll tell you the same thing I told my wife. If you want to worry that much, I'll cancel the insurance. I don't want to pay you to worry AND worry myself. You are right. If I wanted to steal it, it would be long gone. My hesitation for it's removal is that I am too lazy to do it. However, if the system broke, I'd definitely remove it.

vl5150

I edited my post. It was early when I typed it. Before the bypass it wouldn't crank.
Quote:
Originally Posted by vl5150 View Post
To answer the question above, with the starter bypass, the car didn't crank

Originally posted by Vetteoz:
Something was wrong.
With the starter relay bypassed , VATS has no influence on the starter operation

leesvet

why go thru all that when you can buy a bypass module for $15 and simply plug it in where the VATS module lives?

I went the distance and installed a switch for security that kills efi when tripped. The switch can be hidden anywhere you wish..or just install the bypass and go about your bidness like it were an avg car that never had a security system.

I still do not understand why people freak out over VATS. its like ANY other car part. They wear out and stop you from driving. I've never seen anyone try to bypass having tires when those wear out or go flat. Or use something other than spark plugs when those go bad.
Why not just FIX it? parts are available, its not as hard as going thru all these gyrations and you still have a real hard to defeat SECURITY system....

I don't get whats hard about fixing something right. BECAUSE, when you jury rig these home made VATS go around systems, then you totally screw up future diagnostics on other things...like starters, key ign switches, etc. How can you tell what is malfunctioning if you have stuff goofy bypassed and band-aided? The virtues of doing it right are endless...

Yes, I have a bypass that's in there for the time being until I have time to put the new module in. Bypass was available right then, module was a week away...bypass won that race. Got both and will keep both, JIC

parts fail, when they do, just replace them, don't try to re-engineer the thing.

vetteoz

Because it does not address the problem vl5150 alluded to ; the failure of the starter enable relay

The VATS resistor bypass only works if all the VATS related components are functional
All it does is "fool" the module into "thinking" the correct key is being used in the Ign . A cure for a key read failure , nothing else.

If however, you are talking about the fuel enable signal generator that vl5150 installed , the same applies.
All it does is supply the required fuel enable signal to the ECM so it will pulse the injectors , it does nothing for a starter relay related problem