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I need a walkthrough for tuning out VATS

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Old Aug 26, 2011 | 04:06 PM
  #1  
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Default I need a walkthrough for tuning out VATS

Hi guys,

I've been living out of my car in Portland, OR for a month or so. My vehicle is a 1999 Pontiac Firebird with a v6 engine. The car died on the side of the road, likely with a bad fuel pump. At that point, I could crank the starter but the engine would not fire. Holding a gas-soaked rag in the air intake made it get a little further - you could hear it try to fire. Cycling the ignition did not make any audible fuel pump noise at my fuel port.

I left the car at a shop for a few days, then got it towed to a cheaper shop. When it arrived at the second shop, the starter no longer cranked. The second shop brought in an alarms tech, who diagnosed that the VATS system has locked down the car and it will need to be cleared by a dealer.

I have not resistor modded my ignition key wires. I don't know if the key is worn too much. I built a bypass circuit that accepts the +12V starter signal and outputs a 50Hz Fuel Enable signal, and I took my panels off and found the BCM. However, after hours of research, I haven't found anything that explains which wires I need to cut to install the bypass circuit. There are three connectors plugged into the bottom of the BCM - two have six large wires and one has 20+ small wires.

The only documentation I have found referred to these pinouts, which did not appear to match the wires I saw on the 20+ pin connector:
Originally Posted by internet
Code:
--------------------------------------------------
A1 ORN constant hot
A2 PNK hot in run, bulb test, or park
A3 DK BLU fuel enable signal (to pcm)
A4 YEL/BLK starter enable relay control
A5 GRY security indicator enable control
A6
A7
A8
--------------------------------------------------
B1
B2
B3
B4
B5 BLK ground
B6
B7 PPL/WHT ignition pellet return
B8 WHT/BLK ignition pellet feed
--------------------------------------------------
I did find many references to people simply tuning out VATS. Can I fix my problem with a soft mod with tuning software? I'm looking for someone who has HP Tuners, LS1 Edit, or EFI Tuner in the Portland area. Will any of these be adequate to fix my problem? Will the guy who owns the tuner need to have specific knowledge of what hex addresses should be set to what hex values? Where can I find a walkthrough for this?

Thanks guys
-plato
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Old Aug 26, 2011 | 04:53 PM
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Not sure about the v6 pcms but it doesn't matter...your issue is not a VATS issue. VATS will let the car start and run for a few seconds then kill it.

You have some other problem.
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Old Aug 26, 2011 | 05:10 PM
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The starter cranks if we bypass the starter relay and power it directly.

Also I have never seen a 'security' light on my dash at all, and like I said, I think my fuel pump is bad as well as this new issue.

When I turn my key to Run, my dash lights flick on but the starter doesn't fire. I don't remember if the lights stay on or go off. I have had brownout conditions in this car before and I'm not certain the battery's good, although the shop says it is.

I am basically unemployed and homeless right now, I would really like to fix this asap for an interview on Monday.

My questions still stand - I would like to find a photo or detailed explanation of which wires in the 20+ wire connector are VATS bypass related, and I would like to get instructions on tuning out VATS.
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Old Aug 26, 2011 | 06:40 PM
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From: tulsa
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If you are wanting to do the resistor mod you need to be looking under the column. There is a small orange conduit that holds 2 wires. One is white, the other is purple and white if I remember correctly. Regardless all you need to do is find the orange conduit, it has a connector, disconnect it and install you resistor. If you aren't sure which resistor you need, use a volt meter and check the ohms on the pellet in your key then buy the same resistor from radio shak.

That will cover bypassing the key part of the vats system. If the BCM is actually the problem then you need to bypass the relay as well. There are 2 relays located very close to the BCM. You wont see them you'll just have to feel around. One controls fuel and I cant remember what the other one does. I want to say the second one controls the hatch release. Either way, bypass both of them if you have to (paper clips work great for these types of relays, just bend it into a "U" shape and stick it between the 2 terminals that connect when the relay nails up.) There will be a diagram on the relay showing which 2 terminals make contact. Stick the paper clip there.

There is a fuel pump relay in the drivers kick panel area as well. You can do the paper clip trick on it also to nail up the pump if you are in question of it.

My security light never did what everyone said it was supposed to do but I did have a security issue. Both the key and BCM needed to be bypassed in my case.

The info I gave you is based on a LT1 V8 car but I'm pretty sure the VATS is the same on all of the 4th gens. Shoebox's website has a ton of info and pics. Look there if you need more help.

And yes the vats can be tuned out completely with software.
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