a) a "lerning" experience

b) fairly expensive

Had a "no start" today with no DTCs stored.
Checked the voltage to the coil and it started
out at 12 then went to zero. I.e. the Automatic
Shutdown Relay was turning the engine off. :/

Checked a bunch of things again... thought about
the coil but then thought it should also be getting
voltage so there MUST be another problem.

Frustration sets in so I have it towed to the
closest Jeep dealer $89 foo.. I have it taken
down.

Well, the dealer said it would probably be the next
day so I'm getting ready to leave when the mechanics
start gathering around the hood. Seems they found
the supercharger. :) Long story short the head wrencher
starts working on the ZJ. I tell him all the stuff I checked
and he sets to check them again. That's when I find out if
the engine doesn't successfully start in the first few revs
the ASD shuts the ignition down! Well..dammit. It WAS the
coil just as I thought. An Autozone $45 part.

So the dealer puts in the OEM $75 one and bills $138 for labor.
(that's ok. I needed the part and the mechanic taught me a LOT
about how to read a scope and diagnose spark and injectors.)
I call it cheap education.

It also makes the sting hurt a bit less.


--
DougW
Your never too old to be stupid. :)

 

Hi Doug,
It's been kind of telling you to check it, remember you said it
would occasionally miss fire? If you can't find a bad plug, or ignition
wire, rotor, cap, connection, the coil is next in line. And I forgot to
show you the coil oscillation looks like:
http://www.----------.com/coilTest.jpg
God Bless America, ßill O|||||||O
mailto:--------------------

DougW wrote:
>
> a) a "lerning" experience
>
> b) fairly expensive
>
> Had a "no start" today with no DTCs stored.
> Checked the voltage to the coil and it started
> out at 12 then went to zero. I.e. the Automatic
> Shutdown Relay was turning the engine off. :/
>
> Checked a bunch of things again... thought about
> the coil but then thought it should also be getting
> voltage so there MUST be another problem.
>
> Frustration sets in so I have it towed to the
> closest Jeep dealer $89 foo.. I have it taken
> down.
>
> Well, the dealer said it would probably be the next
> day so I'm getting ready to leave when the mechanics
> start gathering around the hood. Seems they found
> the supercharger. :) Long story short the head wrencher
> starts working on the ZJ. I tell him all the stuff I checked
> and he sets to check them again. That's when I find out if
> the engine doesn't successfully start in the first few revs
> the ASD shuts the ignition down! Well..dammit. It WAS the
> coil just as I thought. An Autozone $45 part.
>
> So the dealer puts in the OEM $75 one and bills $138 for labor.
> (that's ok. I needed the part and the mechanic taught me a LOT
> about how to read a scope and diagnose spark and injectors.)
> I call it cheap education.
>
> It also makes the sting hurt a bit less.
>
> --
> DougW
> Your never too old to be stupid. :)

 

Hi Doug,
It's been kind of telling you to check it, remember you said it
would occasionally miss fire? If you can't find a bad plug, or ignition
wire, rotor, cap, connection, the coil is next in line. And I forgot to
show you the coil oscillation looks like:
http://www.----------.com/coilTest.jpg
God Bless America, ßill O|||||||O
mailto:--------------------

DougW wrote:
>
> a) a "lerning" experience
>
> b) fairly expensive
>
> Had a "no start" today with no DTCs stored.
> Checked the voltage to the coil and it started
> out at 12 then went to zero. I.e. the Automatic
> Shutdown Relay was turning the engine off. :/
>
> Checked a bunch of things again... thought about
> the coil but then thought it should also be getting
> voltage so there MUST be another problem.
>
> Frustration sets in so I have it towed to the
> closest Jeep dealer $89 foo.. I have it taken
> down.
>
> Well, the dealer said it would probably be the next
> day so I'm getting ready to leave when the mechanics
> start gathering around the hood. Seems they found
> the supercharger. :) Long story short the head wrencher
> starts working on the ZJ. I tell him all the stuff I checked
> and he sets to check them again. That's when I find out if
> the engine doesn't successfully start in the first few revs
> the ASD shuts the ignition down! Well..dammit. It WAS the
> coil just as I thought. An Autozone $45 part.
>
> So the dealer puts in the OEM $75 one and bills $138 for labor.
> (that's ok. I needed the part and the mechanic taught me a LOT
> about how to read a scope and diagnose spark and injectors.)
> I call it cheap education.
>
> It also makes the sting hurt a bit less.
>
> --
> DougW
> Your never too old to be stupid. :)

 

Hi Doug,
It's been kind of telling you to check it, remember you said it
would occasionally miss fire? If you can't find a bad plug, or ignition
wire, rotor, cap, connection, the coil is next in line. And I forgot to
show you the coil oscillation looks like:
http://www.----------.com/coilTest.jpg
God Bless America, ßill O|||||||O
mailto:--------------------

DougW wrote:
>
> a) a "lerning" experience
>
> b) fairly expensive
>
> Had a "no start" today with no DTCs stored.
> Checked the voltage to the coil and it started
> out at 12 then went to zero. I.e. the Automatic
> Shutdown Relay was turning the engine off. :/
>
> Checked a bunch of things again... thought about
> the coil but then thought it should also be getting
> voltage so there MUST be another problem.
>
> Frustration sets in so I have it towed to the
> closest Jeep dealer $89 foo.. I have it taken
> down.
>
> Well, the dealer said it would probably be the next
> day so I'm getting ready to leave when the mechanics
> start gathering around the hood. Seems they found
> the supercharger. :) Long story short the head wrencher
> starts working on the ZJ. I tell him all the stuff I checked
> and he sets to check them again. That's when I find out if
> the engine doesn't successfully start in the first few revs
> the ASD shuts the ignition down! Well..dammit. It WAS the
> coil just as I thought. An Autozone $45 part.
>
> So the dealer puts in the OEM $75 one and bills $138 for labor.
> (that's ok. I needed the part and the mechanic taught me a LOT
> about how to read a scope and diagnose spark and injectors.)
> I call it cheap education.
>
> It also makes the sting hurt a bit less.
>
> --
> DougW
> Your never too old to be stupid. :)

 

Hi Doug,
It's been kind of telling you to check it, remember you said it
would occasionally miss fire? If you can't find a bad plug, or ignition
wire, rotor, cap, connection, the coil is next in line. And I forgot to
show you the coil oscillation looks like:
http://www.----------.com/coilTest.jpg
God Bless America, ßill O|||||||O
mailto:--------------------

DougW wrote:
>
> a) a "lerning" experience
>
> b) fairly expensive
>
> Had a "no start" today with no DTCs stored.
> Checked the voltage to the coil and it started
> out at 12 then went to zero. I.e. the Automatic
> Shutdown Relay was turning the engine off. :/
>
> Checked a bunch of things again... thought about
> the coil but then thought it should also be getting
> voltage so there MUST be another problem.
>
> Frustration sets in so I have it towed to the
> closest Jeep dealer $89 foo.. I have it taken
> down.
>
> Well, the dealer said it would probably be the next
> day so I'm getting ready to leave when the mechanics
> start gathering around the hood. Seems they found
> the supercharger. :) Long story short the head wrencher
> starts working on the ZJ. I tell him all the stuff I checked
> and he sets to check them again. That's when I find out if
> the engine doesn't successfully start in the first few revs
> the ASD shuts the ignition down! Well..dammit. It WAS the
> coil just as I thought. An Autozone $45 part.
>
> So the dealer puts in the OEM $75 one and bills $138 for labor.
> (that's ok. I needed the part and the mechanic taught me a LOT
> about how to read a scope and diagnose spark and injectors.)
> I call it cheap education.
>
> It also makes the sting hurt a bit less.
>
> --
> DougW
> Your never too old to be stupid. :)

 

L.W. (ßill) ------ III did pass the time by typing:
> Hi Doug,
> It's been kind of telling you to check it, remember you said it
> would occasionally miss fire? If you can't find a bad plug, or ignition
> wire, rotor, cap, connection, the coil is next in line. And I forgot to
> show you the coil oscillation looks like:
> http://www.----------.com/coilTest.jpg

np, that's what the mechanic showed me. He also stated that the number
of oscillations right after burn-time should be > three, anything less and the
coil is starting to have internal shorts.

Also that during burn time there will be several patterns and that can tell
you if there is a fouled plug, a crack, or the gap is way out. And that last
dip after the oscillations is dwell. Got about two pages of notes from the tech.

Now that I understand what to look for this make more sense.
http://members.***.net/wilsond/ign/

Those were just with an old inductive pickup for my timing light
hooked to my lab scope.

I should have just thrown the $39 AutoZone coil at it, but what threw me
was the ASD relay was shutting the system down and that's usually associated
with something being terribly wrong. Now I know better, it shuts down
because it didn't sense the coil or the engine didn't fire after a couple
of revs. Guess the ECU must be looking at the coil ground.

:)

--
DougW
Jeep: Just Empty Every Pocket

 

L.W. (ßill) ------ III did pass the time by typing:
> Hi Doug,
> It's been kind of telling you to check it, remember you said it
> would occasionally miss fire? If you can't find a bad plug, or ignition
> wire, rotor, cap, connection, the coil is next in line. And I forgot to
> show you the coil oscillation looks like:
> http://www.----------.com/coilTest.jpg

np, that's what the mechanic showed me. He also stated that the number
of oscillations right after burn-time should be > three, anything less and the
coil is starting to have internal shorts.

Also that during burn time there will be several patterns and that can tell
you if there is a fouled plug, a crack, or the gap is way out. And that last
dip after the oscillations is dwell. Got about two pages of notes from the tech.

Now that I understand what to look for this make more sense.
http://members.***.net/wilsond/ign/

Those were just with an old inductive pickup for my timing light
hooked to my lab scope.

I should have just thrown the $39 AutoZone coil at it, but what threw me
was the ASD relay was shutting the system down and that's usually associated
with something being terribly wrong. Now I know better, it shuts down
because it didn't sense the coil or the engine didn't fire after a couple
of revs. Guess the ECU must be looking at the coil ground.

:)

--
DougW
Jeep: Just Empty Every Pocket

 

L.W. (ßill) ------ III did pass the time by typing:
> Hi Doug,
> It's been kind of telling you to check it, remember you said it
> would occasionally miss fire? If you can't find a bad plug, or ignition
> wire, rotor, cap, connection, the coil is next in line. And I forgot to
> show you the coil oscillation looks like:
> http://www.----------.com/coilTest.jpg

np, that's what the mechanic showed me. He also stated that the number
of oscillations right after burn-time should be > three, anything less and the
coil is starting to have internal shorts.

Also that during burn time there will be several patterns and that can tell
you if there is a fouled plug, a crack, or the gap is way out. And that last
dip after the oscillations is dwell. Got about two pages of notes from the tech.

Now that I understand what to look for this make more sense.
http://members.***.net/wilsond/ign/

Those were just with an old inductive pickup for my timing light
hooked to my lab scope.

I should have just thrown the $39 AutoZone coil at it, but what threw me
was the ASD relay was shutting the system down and that's usually associated
with something being terribly wrong. Now I know better, it shuts down
because it didn't sense the coil or the engine didn't fire after a couple
of revs. Guess the ECU must be looking at the coil ground.

:)

--
DougW
Jeep: Just Empty Every Pocket

 

L.W. (ßill) ------ III did pass the time by typing:
> Hi Doug,
> It's been kind of telling you to check it, remember you said it
> would occasionally miss fire? If you can't find a bad plug, or ignition
> wire, rotor, cap, connection, the coil is next in line. And I forgot to
> show you the coil oscillation looks like:
> http://www.----------.com/coilTest.jpg

np, that's what the mechanic showed me. He also stated that the number
of oscillations right after burn-time should be > three, anything less and the
coil is starting to have internal shorts.

Also that during burn time there will be several patterns and that can tell
you if there is a fouled plug, a crack, or the gap is way out. And that last
dip after the oscillations is dwell. Got about two pages of notes from the tech.

Now that I understand what to look for this make more sense.
http://members.***.net/wilsond/ign/

Those were just with an old inductive pickup for my timing light
hooked to my lab scope.

I should have just thrown the $39 AutoZone coil at it, but what threw me
was the ASD relay was shutting the system down and that's usually associated
with something being terribly wrong. Now I know better, it shuts down
because it didn't sense the coil or the engine didn't fire after a couple
of revs. Guess the ECU must be looking at the coil ground.

:)

--
DougW
Jeep: Just Empty Every Pocket

 

"DougW" <post.replies@invalid.address> wrote:

> Your never too old to be stupid. :)

My motto is:
When you're stupid you gotta be tough!

( Baptized Clemmie the other day: Had the dog harnessed in on the way for a
run, no top, no doors...big downpour!)

Seahag