Turns Over but Won't Start

"Lanny Chambers" > wrote in message
...
> In article > ,
> "Christopher Muto" > wrote:
>
>> The coil pak registered
>> just 1v instead of 12v and so that was then replaced. Now things seem
>> good
>> again. But no explanation as to what may have cause this failure.
>
> Did your tach vary erratically before the non-startage? The first sign
> of poor grounds is the tach; the final sign is coil pack failure.
>
> --
> Lanny Chambers
> St. Louis, MO
> '94C

Thanks for your input. It operated normally right up to the failure, no
unusual behavior at all. It was raining during the hour drive, so wipers
and headlights were on, but that shouldn't be a problem Then sat parked for
about an hour. Now knowing that it was the coil pack and main relay, my
only thought was perhaps the valve cover gasket might have leaked oil on the
coil pack and caused it to fail, but the mechanic said that shouldn't
happen. So it is a bit of a mystery as to why it happened.

A possible sequence leading to coil pack failure--
The coil pack had a crack or other hermetic seal failure. This can occur at
any place that the molded case has wires or other things that go through the
molded case.
Temperature extremes induce stress due to expansion and contraction
differences between materials. Rapid changes just make matters worse.
Water and water vapor (moisture) was present.
As the engine and coil pack cooled, moisture was drawn into the coil pack.
At the next start attempt, the coil pack shorted out and failed. Or as the
engine compartment heated up moisture inside the coilpack heated up, and
finally reached a part of the coil pack that arced over and then shorted
out.

You would not believe the variety of failures that can occur when high
voltage, solid state devices, moisture, temperature change, and even air
pressure are involved.
A simple and undetected minor production flaw can multiply and cause
failure. One of the common failures is bonding failure between the molded
case and internal parts, or wires that go completely through the molded case
material.


"Christopher Muto" > wrote in message
...
> "Lanny Chambers" > wrote in message
> ...
>> In article > ,
>> "Christopher Muto" > wrote:
>>
>>> The coil pak registered
>>> just 1v instead of 12v and so that was then replaced. Now things seem
>>> good
>>> again. But no explanation as to what may have cause this failure.
>>
>> Did your tach vary erratically before the non-startage? The first sign
>> of poor grounds is the tach; the final sign is coil pack failure.
>>
>> --
>> Lanny Chambers
>> St. Louis, MO
>> '94C
>
> Thanks for your input. It operated normally right up to the failure, no
> unusual behavior at all. It was raining during the hour drive, so wipers
> and headlights were on, but that shouldn't be a problem Then sat parked
> for about an hour. Now knowing that it was the coil pack and main relay,
> my only thought was perhaps the valve cover gasket might have leaked oil
> on the coil pack and caused it to fail, but the mechanic said that
> shouldn't happen. So it is a bit of a mystery as to why it happened.
>

Chuck, Again you impress me. What do you do for a living and in what part of
the world? I'm guessing engineer but maybe that's too obvious. So, what is
it?

Chris
99BBB

"Chuck" > wrote in message
...
>A possible sequence leading to coil pack failure--
> The coil pack had a crack or other hermetic seal failure. This can occur
> at any place that the molded case has wires or other things that go
> through the molded case.
> Temperature extremes induce stress due to expansion and contraction
> differences between materials. Rapid changes just make matters worse.
> Water and water vapor (moisture) was present.
> As the engine and coil pack cooled, moisture was drawn into the coil pack.
> At the next start attempt, the coil pack shorted out and failed. Or as the
> engine compartment heated up moisture inside the coilpack heated up, and
> finally reached a part of the coil pack that arced over and then shorted
> out.
>
> You would not believe the variety of failures that can occur when high
> voltage, solid state devices, moisture, temperature change, and even air
> pressure are involved.
> A simple and undetected minor production flaw can multiply and cause
> failure. One of the common failures is bonding failure between the molded
> case and internal parts, or wires that go completely through the molded
> case material.
>
>
> "Christopher Muto" > wrote in message
> ...
>> "Lanny Chambers" > wrote in message
>> ...
>>> In article > ,
>>> "Christopher Muto" > wrote:
>>>
>>>> The coil pak registered
>>>> just 1v instead of 12v and so that was then replaced. Now things seem
>>>> good
>>>> again. But no explanation as to what may have cause this failure.
>>>
>>> Did your tach vary erratically before the non-startage? The first sign
>>> of poor grounds is the tach; the final sign is coil pack failure.
>>>
>>> --
>>> Lanny Chambers
>>> St. Louis, MO
>>> '94C
>>
>> Thanks for your input. It operated normally right up to the failure, no
>> unusual behavior at all. It was raining during the hour drive, so wipers
>> and headlights were on, but that shouldn't be a problem Then sat parked
>> for about an hour. Now knowing that it was the coil pack and main relay,
>> my only thought was perhaps the valve cover gasket might have leaked oil
>> on the coil pack and caused it to fail, but the mechanic said that
>> shouldn't happen. So it is a bit of a mystery as to why it happened.
>>
>
>

What do I do for a living? As little as possible, since I'm retired! (heh!)

Anyway, At various times in my working years

Navy Shipboard-- (Vietnam) electronics tech, com & nav
GE engineering lab tech, QC automated systems specialist (mil spec
environmental & computerized testing)
B1A Design Team (electronics systems test & equipment design)
Hallicrafters/Northrop Field Engineer, F-15 special purpose electronics,
Germany, US)
Contractor, DOD/USAF special purpose avionics, systems management &
technical support. (F-15, F-16, B-52 and others)
In the late 90's, the in-house government line might be answered with the
deepest gravelly voice you ever heard-- Warfare (short pause) We deliver.

You asked!


"Chris D'Agnolo" > wrote in message
...
> Chuck, Again you impress me. What do you do for a living and in what part
> of the world? I'm guessing engineer but maybe that's too obvious. So, what
> is it?
>
> Chris
> 99BBB
>
> "Chuck" > wrote in message
> ...
>>A possible sequence leading to coil pack failure--
>> The coil pack had a crack or other hermetic seal failure. This can occur
>> at any place that the molded case has wires or other things that go
>> through the molded case.
>> Temperature extremes induce stress due to expansion and contraction
>> differences between materials. Rapid changes just make matters worse.
>> Water and water vapor (moisture) was present.
>> As the engine and coil pack cooled, moisture was drawn into the coil
>> pack.
>> At the next start attempt, the coil pack shorted out and failed. Or as
>> the engine compartment heated up moisture inside the coilpack heated up,
>> and finally reached a part of the coil pack that arced over and then
>> shorted out.
>>
>> You would not believe the variety of failures that can occur when high
>> voltage, solid state devices, moisture, temperature change, and even air
>> pressure are involved.
>> A simple and undetected minor production flaw can multiply and cause
>> failure. One of the common failures is bonding failure between the molded
>> case and internal parts, or wires that go completely through the molded
>> case material.
>>
>>
>> "Christopher Muto" > wrote in message
>> ...
>>> "Lanny Chambers" > wrote in message
>>> ...
>>>> In article > ,
>>>> "Christopher Muto" > wrote:
>>>>
>>>>> The coil pak registered
>>>>> just 1v instead of 12v and so that was then replaced. Now things seem
>>>>> good
>>>>> again. But no explanation as to what may have cause this failure.
>>>>
>>>> Did your tach vary erratically before the non-startage? The first sign
>>>> of poor grounds is the tach; the final sign is coil pack failure.
>>>>
>>>> --
>>>> Lanny Chambers
>>>> St. Louis, MO
>>>> '94C
>>>
>>> Thanks for your input. It operated normally right up to the failure, no
>>> unusual behavior at all. It was raining during the hour drive, so
>>> wipers and headlights were on, but that shouldn't be a problem Then sat
>>> parked for about an hour. Now knowing that it was the coil pack and
>>> main relay, my only thought was perhaps the valve cover gasket might
>>> have leaked oil on the coil pack and caused it to fail, but the mechanic
>>> said that shouldn't happen. So it is a bit of a mystery as to why it
>>> happened.
>>>
>>
>>
>

Wow, I love it! However;

"Warfare (short pause) We deliver."

is more than a bit scary!

Thanks,
Chris
BBB


"Chuck" > wrote in message
...
> What do I do for a living? As little as possible, since I'm retired!
> (heh!)
>
> Anyway, At various times in my working years
>
> Navy Shipboard-- (Vietnam) electronics tech, com & nav
> GE engineering lab tech, QC automated systems specialist (mil spec
> environmental & computerized testing)
> B1A Design Team (electronics systems test & equipment design)
> Hallicrafters/Northrop Field Engineer, F-15 special purpose electronics,
> Germany, US)
> Contractor, DOD/USAF special purpose avionics, systems management &
> technical support. (F-15, F-16, B-52 and others)
> In the late 90's, the in-house government line might be answered with the
> deepest gravelly voice you ever heard-- Warfare (short pause) We deliver.
>
> You asked!
>
>
> "Chris D'Agnolo" > wrote in message
> ...
>> Chuck, Again you impress me. What do you do for a living and in what part
>> of the world? I'm guessing engineer but maybe that's too obvious. So,
>> what is it?
>>
>> Chris
>> 99BBB
>>
>> "Chuck" > wrote in message
>> ...
>>>A possible sequence leading to coil pack failure--
>>> The coil pack had a crack or other hermetic seal failure. This can occur
>>> at any place that the molded case has wires or other things that go
>>> through the molded case.
>>> Temperature extremes induce stress due to expansion and contraction
>>> differences between materials. Rapid changes just make matters worse.
>>> Water and water vapor (moisture) was present.
>>> As the engine and coil pack cooled, moisture was drawn into the coil
>>> pack.
>>> At the next start attempt, the coil pack shorted out and failed. Or as
>>> the engine compartment heated up moisture inside the coilpack heated up,
>>> and finally reached a part of the coil pack that arced over and then
>>> shorted out.
>>>
>>> You would not believe the variety of failures that can occur when high
>>> voltage, solid state devices, moisture, temperature change, and even air
>>> pressure are involved.
>>> A simple and undetected minor production flaw can multiply and cause
>>> failure. One of the common failures is bonding failure between the
>>> molded case and internal parts, or wires that go completely through the
>>> molded case material.
>>>
>>>
>>> "Christopher Muto" > wrote in message
>>> ...
>>>> "Lanny Chambers" > wrote in message
>>>> ...
>>>>> In article > ,
>>>>> "Christopher Muto" > wrote:
>>>>>
>>>>>> The coil pak registered
>>>>>> just 1v instead of 12v and so that was then replaced. Now things
>>>>>> seem good
>>>>>> again. But no explanation as to what may have cause this failure.
>>>>>
>>>>> Did your tach vary erratically before the non-startage? The first sign
>>>>> of poor grounds is the tach; the final sign is coil pack failure.
>>>>>
>>>>> --
>>>>> Lanny Chambers
>>>>> St. Louis, MO
>>>>> '94C
>>>>
>>>> Thanks for your input. It operated normally right up to the failure,
>>>> no unusual behavior at all. It was raining during the hour drive, so
>>>> wipers and headlights were on, but that shouldn't be a problem Then
>>>> sat parked for about an hour. Now knowing that it was the coil pack
>>>> and main relay, my only thought was perhaps the valve cover gasket
>>>> might have leaked oil on the coil pack and caused it to fail, but the
>>>> mechanic said that shouldn't happen. So it is a bit of a mystery as to
>>>> why it happened.
>>>>
>>>
>>>
>>
>
>

The whole place was a bit scary at times. Let's just say that I've had my
fill of windowless buildings, labs & rooms with bank vault doors, electronic
badges, calls from a multi sided building, phones with cards and two keys,
etc. Not to mention quiet disagreements with airport/airline security and
customs as to what they could and could not open, inspect, x-ray, etc. (The
right paperwork wins every time.)

As to cars, I started working on them in the days when most custom work was
done by the car owner with lots of help from friends. During vacations from
school (1960's), I worked for a small town "welding and machine shop" that
did major repair of just about anything from farm equipment to rebuilding
light aircraft. We had a mix of talents available, from the certified master
welder that owned the shop to various A&E mechanics, FAA inspectors, and
automotive body & paint specialists. There were two brothers that were
experts in recovering fabric covered aircraft. A side business was running
the "insurance pool" for the southern half of the state, and a wrecker
service that was on the state police approved list. We built a private
airport with rental hangars that is still there, and last I heard, still
owned by the 96 year old widow of the shop owner and their children..

"Warfare (short pause) We deliver." Imagine a voice about two octaves lower
than the one in the old song "sixteen tons". It sent chills down your
spine.
Replies from those who called in error were usually quite funny, or dead
silence, followed by a quick apology!

"Chris D'Agnolo" > wrote in message
...
> Wow, I love it! However;
>
> "Warfare (short pause) We deliver."
>
> is more than a bit scary!
>
> Thanks,
> Chris
> BBB
>
>
> "Chuck" > wrote in message
> ...
>> What do I do for a living? As little as possible, since I'm retired!
>> (heh!)
>>
>> Anyway, At various times in my working years
>>
>> Navy Shipboard-- (Vietnam) electronics tech, com & nav
>> GE engineering lab tech, QC automated systems specialist (mil spec
>> environmental & computerized testing)
>> B1A Design Team (electronics systems test & equipment design)
>> Hallicrafters/Northrop Field Engineer, F-15 special purpose electronics,
>> Germany, US)
>> Contractor, DOD/USAF special purpose avionics, systems management &
>> technical support. (F-15, F-16, B-52 and others)
>> In the late 90's, the in-house government line might be answered with the
>> deepest gravelly voice you ever heard-- Warfare (short pause) We deliver.
>>
>> You asked!
>>
>>
>> "Chris D'Agnolo" > wrote in message
>> ...
>>> Chuck, Again you impress me. What do you do for a living and in what
>>> part of the world? I'm guessing engineer but maybe that's too obvious.
>>> So, what is it?
>>>
>>> Chris
>>> 99BBB
>>>
>>> "Chuck" > wrote in message
>>> ...
>>>>A possible sequence leading to coil pack failure--
>>>> The coil pack had a crack or other hermetic seal failure. This can
>>>> occur at any place that the molded case has wires or other things that
>>>> go through the molded case.
>>>> Temperature extremes induce stress due to expansion and contraction
>>>> differences between materials. Rapid changes just make matters worse.
>>>> Water and water vapor (moisture) was present.
>>>> As the engine and coil pack cooled, moisture was drawn into the coil
>>>> pack.
>>>> At the next start attempt, the coil pack shorted out and failed. Or as
>>>> the engine compartment heated up moisture inside the coilpack heated
>>>> up, and finally reached a part of the coil pack that arced over and
>>>> then shorted out.
>>>>
>>>> You would not believe the variety of failures that can occur when high
>>>> voltage, solid state devices, moisture, temperature change, and even
>>>> air pressure are involved.
>>>> A simple and undetected minor production flaw can multiply and cause
>>>> failure. One of the common failures is bonding failure between the
>>>> molded case and internal parts, or wires that go completely through the
>>>> molded case material.
>>>>
>>>>
>>>> "Christopher Muto" > wrote in message
>>>> ...
>>>>> "Lanny Chambers" > wrote in message
>>>>> ...
>>>>>> In article > ,
>>>>>> "Christopher Muto" > wrote:
>>>>>>
>>>>>>> The coil pak registered
>>>>>>> just 1v instead of 12v and so that was then replaced. Now things
>>>>>>> seem good
>>>>>>> again. But no explanation as to what may have cause this failure.
>>>>>>
>>>>>> Did your tach vary erratically before the non-startage? The first
>>>>>> sign
>>>>>> of poor grounds is the tach; the final sign is coil pack failure.
>>>>>>
>>>>>> --
>>>>>> Lanny Chambers
>>>>>> St. Louis, MO
>>>>>> '94C
>>>>>
>>>>> Thanks for your input. It operated normally right up to the failure,
>>>>> no unusual behavior at all. It was raining during the hour drive, so
>>>>> wipers and headlights were on, but that shouldn't be a problem Then
>>>>> sat parked for about an hour. Now knowing that it was the coil pack
>>>>> and main relay, my only thought was perhaps the valve cover gasket
>>>>> might have leaked oil on the coil pack and caused it to fail, but the
>>>>> mechanic said that shouldn't happen. So it is a bit of a mystery as
>>>>> to why it happened.
>>>>>
>>>>
>>>>
>>>
>>
>>
>

Chuck, That is interesting to read. Thank you for writing it. Though I
only looked at the old coil pack briefly, it looked remarkably clean and
intact. I say remarkable since it was over 14 years old and had 130,000
miles on it. Certainly nothing jumped out as an obvious point of failure.
The issue must have been internal and probably due to what you suggest. It
was indeed a cool and humid (raining) day and the engine was certainly hot
after the long drive. Though the engine compartment appeared bone dry when
I popped the hood to investigate, the humidity in the air was undeniable.
Thanks again for your insights.

"Chuck" > wrote in message
...
>A possible sequence leading to coil pack failure--
> The coil pack had a crack or other hermetic seal failure. This can occur
> at any place that the molded case has wires or other things that go
> through the molded case.
> Temperature extremes induce stress due to expansion and contraction
> differences between materials. Rapid changes just make matters worse.
> Water and water vapor (moisture) was present.
> As the engine and coil pack cooled, moisture was drawn into the coil pack.
> At the next start attempt, the coil pack shorted out and failed. Or as the
> engine compartment heated up moisture inside the coilpack heated up, and
> finally reached a part of the coil pack that arced over and then shorted
> out.
>
> You would not believe the variety of failures that can occur when high
> voltage, solid state devices, moisture, temperature change, and even air
> pressure are involved.
> A simple and undetected minor production flaw can multiply and cause
> failure. One of the common failures is bonding failure between the molded
> case and internal parts, or wires that go completely through the molded
> case material.
>
>
> "Christopher Muto" > wrote in message
> ...
>> "Lanny Chambers" > wrote in message
>> ...
>>> In article > ,
>>> "Christopher Muto" > wrote:
>>>
>>>> The coil pak registered
>>>> just 1v instead of 12v and so that was then replaced. Now things seem
>>>> good
>>>> again. But no explanation as to what may have cause this failure.
>>>
>>> Did your tach vary erratically before the non-startage? The first sign
>>> of poor grounds is the tach; the final sign is coil pack failure.
>>>
>>> --
>>> Lanny Chambers
>>> St. Louis, MO
>>> '94C
>>
>> Thanks for your input. It operated normally right up to the failure, no
>> unusual behavior at all. It was raining during the hour drive, so wipers
>> and headlights were on, but that shouldn't be a problem Then sat parked
>> for about an hour. Now knowing that it was the coil pack and main relay,
>> my only thought was perhaps the valve cover gasket might have leaked oil
>> on the coil pack and caused it to fail, but the mechanic said that
>> shouldn't happen. So it is a bit of a mystery as to why it happened.
>>
>
>

Lanny,
I got the car back last Friday and drove it home. It seemed a bit happier
than usual, but perhaps that was just me.
Left it parked for three days. When I went to use it, it started right up,
but then once I started driving the tach would drop randomly and so I kept
shifting into neutral to give it gas and keep it from stalling. After about
five minuets this cleared up. When stopped at a light the tach was steady
but I did feel a minor roughness to the idle. Two days later when I went to
use it again the same thing happened and it actually stalled as I wanted to
see what it might do without me goosing the gas. Started back up again and
ran ok after a few minuets.
Does this fit your description of erratic tach caused by a poor ground
connection someplace? Any place in particular that I should look for a bad
ground connection?
Many thanks.

"Lanny Chambers" > wrote in message
...
> In article > ,
> "Christopher Muto" > wrote:
>
>> The coil pak registered
>> just 1v instead of 12v and so that was then replaced. Now things seem
>> good
>> again. But no explanation as to what may have cause this failure.
>
> Did your tach vary erratically before the non-startage? The first sign
> of poor grounds is the tach; the final sign is coil pack failure.
>
> --
> Lanny Chambers
> St. Louis, MO
> '94C

Does this fit your description of erratic tach caused by a poor ground
> connection someplace?

I think it does Christopher. At least it does not seem inconsistent with
what the bad ground would act like, in my opinion.

Chris
99BBB

"Christopher Muto" > wrote in message
t...
> Lanny,
> I got the car back last Friday and drove it home. It seemed a bit happier
> than usual, but perhaps that was just me.
> Left it parked for three days. When I went to use it, it started right
> up, but then once I started driving the tach would drop randomly and so I
> kept shifting into neutral to give it gas and keep it from stalling.
> After about five minuets this cleared up. When stopped at a light the
> tach was steady but I did feel a minor roughness to the idle. Two days
> later when I went to use it again the same thing happened and it actually
> stalled as I wanted to see what it might do without me goosing the gas.
> Started back up again and ran ok after a few minuets.
> Does this fit your description of erratic tach caused by a poor ground
> connection someplace? Any place in particular that I should look for a
> bad ground connection?
> Many thanks.
>
> "Lanny Chambers" > wrote in message
> ...
>> In article > ,
>> "Christopher Muto" > wrote:
>>
>>> The coil pak registered
>>> just 1v instead of 12v and so that was then replaced. Now things seem
>>> good
>>> again. But no explanation as to what may have cause this failure.
>>
>> Did your tach vary erratically before the non-startage? The first sign
>> of poor grounds is the tach; the final sign is coil pack failure.
>>
>> --
>> Lanny Chambers
>> St. Louis, MO
>> '94C
>
>

In article > ,
"Christopher Muto" > wrote:

> Does this fit your description of erratic tach caused by a poor ground
> connection someplace?

Yes, if the tach doesn't seem to agree with the actual rpm of the
engine; i.e., the tach droops but the engine remains steady.

Heck, clean and tighten your grounds anyway. This is regular preventive
maintenance.

> Any place in particular that I should look for a bad
> ground connection?

Search the NA forum at http://forum.miata.net/ for "cleaning grounds" or
similar. You should find twenty-seven eight-by-ten color glossy
photographs with circles and arrows and a paragraph on the back of each
one...

1.6 cars have somewhat different ground arrangements from 1.8 cars, so
make sure you're looking at the right instructions.

--
Lanny Chambers
St. Louis, MO
'94C