I have had a stalling problem with my 1996 Cadillac Deville concourse.
It is very sporadic and only stalls at a stop or when coming to a
stop. It will, Luckily, restart up again. The Cadillac dealer has had
me do extensive costly work to it to no avail. WE have done every
thing from replacing fuel pumps ,plugs, wires, you name it, it has been
done . The last time it was in the shop we though we had solved the
problem because the service engine light stated on and needed the EGR
Valve and Mass Air Flow Sensor replaced. But it is still stalling.
DOES ANYONE HAVE AN ANSWER < ALSO HOW CAN I GET IN TOUCH WITH CADILLAC
FOR HELP>

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Request for Question Clarification by alienintelligence-ga on 06 Oct 2002 10:00 PDT

Hi mojo22...

A 96 Caddy should be an OBDII 
emissions control setup. I am
rather intimately involved with
the same type of PCM (engine's
computer) in a vehicle I own.

I've had this same problem before
but it can be caused by a variety
of issues. Yours not necessarily
akin to mine.

In my case it was due to a misfiring
cylinder. Also bad ignition components.

What I wanted to ask you is this.
Have they made a scan of your engine
failing? No dealer should throw parts
at a problem without having a very
obvious pattern of troubles shown 
on a PCM scan log. I say they owe you
some money back for wasting your
time with frivolous repairs if they
aren't making any progress.

If you are getting multiple codes
thrown... the part that is bad is
rarely what codes came up. It sounds
confusing and irrational but it does
make some sense once you understand
what is going on with all the sensors,
etc.

I'd say this could be one of two
things before knowing more... either
the IAC (Idle air controller) or a
bad wiring harness/bad PCM plug. 

Also, what type of ignition is on 
the engine? Any chance its an optispark
unit?

I would presume the engine tries to
shut off when you come off of the
throttle from a speed higher than
a roll? In other words, you were 
applying gas, let off, come to a 
stop, then suddenly the engine lugs
the RPMs hunt a bit and eventually 
the engine quits. You give it a sec,
and it starts right back up, like
nothing was wrong?


Which part of Cadillac did you want
to get hold of? Tech or Customer
Support?


thanks
-AI

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Clarification of Question by mojo22-ga on 06 Oct 2002 17:39 PDT

Thanks All for the siggestions. AI you come the closes to my symptons.
AI The Cadilac Dealer that i have been handling this has mADE SCANS
But nothing shows up if it doess not show a service engine light.
Thats wyy this last time we though that we had found the problem. T Am
going to have them follow up with the lose harnes suggestion.

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Request for Question Clarification by alienintelligence-ga on 07 Oct 2002 00:38 PDT

Hi again mojo22...

Well, the scans I had in mind were more 
diagnostic than "engine codes". Our
engine's computers are rather complex
in their reporting of engine conditions 
and parameters. There really isn't any
malfunction that doesn't have a relevant
"value" on some sensor. The logs that I
get from my vehicle look like this:

[ http://www.alienintelligence.com/misc_files/0-120.htm ]

That one is formatted by Excel, 

this one is the 'raw' dump straight from the PCM

[ http://www.alienintelligence.com/misc_files/0209212220.htm ]

It looks confusing, it is a little...  
but I can read it like a book now.

This is just a fraction of the items available
for logging. Here are some of the other items:

[ http://www.autotap.com/enhanced_parameters_gm.asp ]

Maybe the mechanic should consider getting
more sophisticated equipment?

So it seems like the mechanics are simply
dumping the "engine codes". This is NOT how
you fix a vehicle. Alot of engine problems
do not throw engine lights. The scans that I 
take from my engine are done with a laptop
while I am driving, WHILE the condition is
occurring. You take the scans and "play them
back" when you are done testing. Without a
thorough evaluation like this, the only thing
that can be done is replace parts til someone
gives up or they stumble over the answer.

What city/state are you in? Maybe I could
recommend a mechanic with a bit more proficiency
at repairing than replacing.


-AI

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Clarification of Question by mojo22-ga on 07 Oct 2002 07:26 PDT

AI thanks for all your help.I am In BAKERSFIELD, Ca 93308.

Could you let me know how to get in touch with Cadilac bothj Customer
and Tech support.

I had a 1996 Cadillac, and when it was new, my wife and I took a trip
from Southern California to Idaho. About every 100 miles, the motor
would sputter and stop.  I would wait about 10 minutes, and the motor
would start and go for about another 100 miles.  I finally found a
mechanic that knew what he was doing, and fixed it with a new “fuel
sock”.  He said, the fuel sock, was a fuel line gas filter, and this
problem was common with the Cadillac.

I bought an old car for $300 and it had stalling problems, and it took
us 2 years, many visits, and lots of cash and tears to find that it
had burnt wires...they were burnt just enough that it didn't have full
connection.  That was replaced...and, ouila, no more problems.      
Another car I had it stalled out when I made a left turn....that was
the time something was pressing on the wires and cutting the current. 
The last problem with my car was the starting and dieing, and it
turned out to be that it needed new spark plugs.  Hopefully my car
problems would be answers for your car problems.

sorry about having to add this additional comment but, you might want
to check out the starter.....if you have replaced one, maybe the batch
of them from the store are all bad.....sometimes they sell you new
ones when in reality they are refurbished starters, and they can get a
bad batch in....try another supplier.  Also, if you've been going to
the same mechanic for solving all your car problems, then change
mechanics...or ask the teenager next door for their comments.

Have the mechanic (or yourself, if you feel up to it) check the
throttle body for carbon build-up.  The butterfly valve inside the
throttle body is in the closed position when the gas pedal is not
pressed.  There is only a small gap to allow just enough air into the
motor for idling.  As the gas pedal is pressed the valve opens
allowing more air in.  If there is a build-up of carbon, sludge, etc.
there may not be enough passage of air for proper idling.

To clean the throttle body / butterfly valve get a carburetor cleaner
that is "Sensor Safe."  This means that it won't harm the Throttle
Position Sensor, the Oxygen Sensor or and of the other various sensors
downstream.  To be on the safe side do not spray the cleaner into the
intake.  Instead, spray the cleaner on a paper towel and wipe the area
clean.  Use a Q-tip to get into the tighter areas.  Button it all back
up (be sure to secure the air intake hose) and test drive.

Hope this helps,
Brian