First Post so please be gentile...

I've chased this problem down to what I believe is the VATS.
A little history: 1994 Bonneville - Plain ol' DBeater
Started and ran great for the longest time. Condition began occassionally while riding down the road the car would just "shut-off" for a split second then continue running. Got progressively worse until it stranded me...I was finally able to limp it home tho. Has been in the driveway for 4 months now and wife wants to haul for junk...I can't blame her! Currently will only fire sometimes (cranks fine) after key has been in ignition in RUN position for sometime (a trick learned while reading about VATS and tracing what I had done when it HAD fired)

NOTE: spark at plugs and car will fire/start if ether is sprayed into throttle body so I've "eliminated" ignition issue.

Read information on the site to diagnose and have been thru the following:
Minimal Fuel Pressure at fuel rail so I changed the fuel pump - no start
Smell of fuel in Fuel Regulator so I replaced it - no start
Read about intermittent CPS issues so I replaced it - no start
Checked voltage and resistance of all injectors and within spec - car starts
belief is the because the key had to be in the run position for period of
time, that lead me to the VATS postings.
HOWEVER, car will NOT start/run on every subsequent start
VATS pellet was measured and VATS bypass made and wired in - no start

Car will still only OCCASSIONALLY run when the key is left in the run position fro some period of time.
I'm now at a loss:
Am I to get a new VATS module that matches pellet?
I've read of some difficulty even identifying the VATS module in dash
Should I get a new VATS module and key cylinder?
Should I build (can I buy) the signal generator to fool the PCM?

Truthfully, I'm sick of the whole thing and would love to have this car running. I need it for many reasons as it is a back-up to other cars when I work on them or loan it to my stepson home from college.

All help appreciated...
thanks
al

If the VATS is working properly, the security light should be giving you some indication if it is VATS related. If the security light stays on, or keeps blinking, that confirms that is the issue, and something is up with the bypass. If the light doesn't even come on, that would have me wondering about it. It should blink a few times and then go out.

If you want to completely remove the VATS, you need something like this:

Baker Electronix - GM VATS Bypass

You would then bypass the starter interrupter, and you should never have to worry about it again. This fix is permanent, as long as the bypass module holds up. There are other examples of bypasses as well, so be sure to shop around. This basically simulates the 'all is well' signal that the VATS sends out, that signals the PCM to fire up the fuel pump.

I should also note, I referenced two different bypasses in my post. The first is the resistor bypass, that is usually used when wires break, or keys wear out. The second bypasses the whole system entirely, and simply causes the computer to think that the VATS is happy.

i would check the signal to the vats signal to the pcm, its possible the pcm is bad too

should be a dc square wave

This sounds like what I went through when my 96' Park Ave broke down.
I replaced pretty much everything that you replaced, and then I got to the MAF Sensor, I thought that VATS was the issue also, but if there is no security light remaining on, then I doubt VATS is the issue.
Check your MAF Sensor out, yours looks like the tip was made on it just like mine was, and that tip can come loose, and it will spin around blocking the air from being metered by the MAF'* thermistors.
That caused an occasional no start for me.
If you find the tip is loose, just remove it, clean the MAF'* thermistors with MAF Sensor cleaner, and replace the MAF ASAP.
A tip, every time you replace your air filter, clean your MAF Sensor.

Has the car had any DTC codes pulled from it recently?

Thanks for the responses guys...Forums with guys with experience are invaluable!
Ironically, after I posted I walked back out, pulled my VATS By-Pass Resistor pack off, reconnected the wires and the thing started...multiple times!

So, I partially buttoned all the panels up and walked away. Just got home...start and die.

I would like to note, the Security light does NOT flash and goes out. Therefore, I talk the last advice given and move to the next step possibly with the MAF Sensor.

But I will also note, there are times while the key is the run position, ALL of the pre-start indicator lights will turn off (Restraint, Security, AntiLock and SES) AND you can hear multiple relays clicking in the firewall fuse box. Also, the fuel pump runs for different lengths of times (which is dependent upon pressure) however, when all lights have turned off I recall it continuing to run.

This gives me thoughts of a PCM...cost and difficulty to replace?
Thoughts?

oh, and sorry, I haven't pulled any codes because all I have is a full function OBDII reader and it goes thru all the connection procedures for the different standards and is never able to communicate with the vehicle.

Also, on the PCM, please tell me what type/kind to look for and I will start trying to find one unless you guys already have a source.

This used to happen to me in my old bonnie. It would shut off while driving and the stupid VATS system would lock me out and leave me stranded. It was a nightmare. Bypassing it worked for me and it isn't difficult to do. I Hope you can get it fixed.

The pellet in your key has a certain resistance. Measure the resistance and match it up with the correct code.

Just solder or clamp in resistors that equal you value of resistance essentially tricking the vats system into think all is well.

Have you checked the vehicles grounds, the clicking could be from a bad ground, or battery that needs charging..
Still check that MAF out.