VATS on a 87 corvette

[Greg Sievers]

I have been stranded too many times lately by this VATS system. I have the
VATS
bypass installed but that did not help. I am thinking now that the module
itself is bad.
I found out that you can disable the VATS by disabling it in the ECM. Has
anybody
done this. I am looking at EEPROM burners and software to make my own CHIP.
I have a Hypertech chip in there now that I want to keep that configuration
just
want to delete the VATS from the config.
Every time I take it out now I get stranded and have to wait 15min to get it
to start.
Needless to say I dont drive it.
Any help in this would be greatly appreciated.

Greg S.

[greybeard]

Is your "VATS bypass" the one with the 4.5K (or 7.5K?)
resistor crossing the ign. key chip contacts?
If so, that's pity because I was just going to install that
"fix" in my 89 rag. My occasional VATS problem is not very
serious, but *always* seems to be at the most awkward times
(I would NEVER try to use a 'vette as a getaway car).

I heard or read somewhere that when the VATS is activated,
presumably by the computer as you say, that the actual timed
total cut off is controlled by a relay "somewhere" around
the computer/AC/Radio? area, but I could never ever find it.
I had just replaced the heater core, and didn't want to
*ever* have to go back in there again. If anyone has any
info. on this, maybe the VATS could be disabled at the
relay???

Any info. greatly appreciated.

TIA

[88 4Fun]

The relay is behind the center console above the radio along with your turn
signal flasher. There's one or two fuses there too.
.
"greybeard" <mister...@yahoo.com> wrote in message
news:3CE96645...@yahoo.com...

[greybeard]

Thanks, Have you ever done anything with it to try and
disable the VATS? Do you know if it will work? Does that
relay have any markings, or?, to help identify which one it
is? I seem to remember all sorts of relays, etc. up in there
when i had the dash out.

Thanks.

[vette...@webtv.net]

You stated you had to wait 15 minutes for it to start....
The VATS resets after approximately 4.5 minutes. Especially since you
have installed the VATS bypass, have you considered the possibility that
you have a "heat soak" starter problem?

[88 4Fun]

I didn't do anything with it. I just know where it is. I don't use the VATS
system, I have a Clifford alarm system that I use instead. I just know where
the relay is along with a fuse or 2, I forget how many that are in that area
too. The relay is black and looks like those on your fan shroud but smaller.

"greybeard" <mister...@yahoo.com> wrote in message

news:3CE9790C...@yahoo.com...

[Ray Quayle]

Hey folks,
Just FYI, on the '86-'88 VATS a VATS Decoder Module is used. It has 1 input
from the ignition cylinder that is the resistance value of your key. The
VATS Decoder Module has 2 outputs. One is an enable ground to the Starter
Enable Relay located behind the DIC (behind the center console above the
radio along with your turn signal flasher as 88 4Fun mentioned). The other
output is a squarewave signal to the ECM. If the ECM sees this squarewave,
it allows injector operation. Grounding the Dark Green wire of the Starter
Enable Relay only defeats half of the VATS system. Your engine will now
crank, but with no fuel, still no start. A custom PROM that ignores the
VATS Signal and always allows injector operation is the other half of the
equation to completely eliminate VATS. The most common problem on these
early VATS cars is the key and the ignition contacts though. This is where
the VATS Bypass Modules come in. They simply supply the VATS Module with
the correct resistance at all times, bypassing the key and ignition
contacts. For more information on this aspect see my page at:
http://www.corvetteforum.net/c4/rayquayle/vats/vats.htm

Also as mentioned by vettefella, the timeout period is 4 minutes. If you
need to wait longer than this for a crank and especially if you hear a
single click each time ignition is switched to start coming from behind the
DIC, your problem is most likely not VATS related. The click you hear
coming from behind the DIC is the Starter Enable Relay energizing. This
means VATS is working correctly and you either have problem with the Clutch
Start Switch if manual (or Park/Neutral Switch if Auto) or the wiring to the
Starter or the Starter/Solenoid itself (Heatsoak).

Hope this helps to clear things up a bit.

--
Ray Quayle in England
'86 Indy PaceCar, 4+3
NCM Founder #2896
NCM Lifetime #672

[mrve...@interstateweb.net]

the best thing an owner can do is get a chip for those cars, and have as one
thing the VATS eliminated....bad enough fighting all the excessive
electronics.... without getting stranded over something useless.....as long as
the theives think you have it...you do...

GENE

--

HOME OF THE BUY-TRONIC VETTE....
WE CAN MODIFY IT, WE HAVE THE TECH......
http://home.att.net/~ncmpics/mrvette.htm

[Greg Sievers]

Thanks for all the information on this subject. Its gotten to the point now
that this is happening every time
I take the car out. I usually wait 10 to 15 minutes to start it because I
dont want to try too soon and start
the process all over again. I will check the Park/Neutral switch since the
car is automatic. I have not heard
the click above the radio area when I try to start it. I got the info to
bypass the relay from someone else,
but reading your message I realize that is only part of it and I need to
bypass the relay and get a custom chip.
The relay bypass is easy, getting the custom made PROM I am having problems
with. I am looking into
making my own and realize there is much more to it than I thought. Anyway,
very good info to know on bypassing
this VATS. Have had problems with it for some time now, but I think it is a
real problem now.

Thanks
Greg

Ray Quayle <ray.q...@btinternet.com> wrote in message
news:ada865$e8s$1...@helle.btinternet.com...

[greybeard]

Hi Ray,

Re: your referencing the VATS on the 86 - 88 models - do you
know if that same info also applies to 89, or were there
some changes?

Thanks.