pick one

"Jim Warman" <mechanic@tenalpsulet.net> wrote in message
news:zpnUd.4997$LN5.3040@edtnps90...
> Ford offers one that works with the WDS. Unfortunately we can only compare
> two cylinders at a time with the adapter. In the Ford COP systems, the PCM
> has direct control over each coil and MA Ford believes that reading primary
> waveform is not required and that all we really need to know is if primary
> current is being switched. (Primary wave form may look like a mirror of
> secondary but because of the difference in winding ratio, it is atually
> showing some very different information). Anyway, there is much to be
> learned from a real time scope sweep which is an uninterrupted trace of
> volts over time. Digital scopes have limitations because of their "scan
> rates"..... the information is read then processed then displayed in a
> continuous rotation allowing many small (very small) gaps in the
> information. Still, the most important information is still there....
> ionization voltage, spark line voltage and spark duration.
>

Fords choice of tools has always been marginal. But by tapping into the coils
fuse with a low current probe ( all the coils share a common fuse ) you can now
see all eight. If you know what cylinder is the suspect cylinder you can easily
just use a low current probe on that one coil. That can be done with a stand
alone inexpensive oscilloscope ( anywhere from 350. to 500. U.S. dollars new
refurbished can be had for less ) no need to buy a very expensive designed for
automotive use scan tool ( just the scan tool for and average cost of 1000. U.S
dollars, then add the extras to use it as a scope ) Even though one can argue
about the differences in looking the primary side or the secondary side of a
coil the overall information is the same if one knows what they are looking at.

> BTW, the Ford method wants us to concentrate on 3 key readings plus (if we
> feel a requirement) the coil "stress" test..... basically an insulation
> test. Personally, I don't like this particular test since it can lead to
> premature coil failure if performed incorrectly.
>
> If we see low ionization voltage and long duration, rich mixtures could be
> one of the causes but it is by no means the only possiblility.... the scope
> is but one tool in our aresnal.
>

One tool but a very good and important one.

> When the GM Quad 4 was first introduced (wasted spark, almost a COP system),
> to hook our scopes up to it, we would unbolt the the top cover and lay it on
> it's back on top of the motor. We would install plug wires between the coil
> towers and the plugs...... if a wire came off during testing, those things
> could pack a real solid punch.
>
>

 

pick one

"aarcuda69062" <nonelson@sbcglobal.net> wrote in message
news:nonelson-E7A565.12410827022005@newsclstr01.news.prodigy.com...
> In article <YqOdnb0pbLxjkL_fRVn-pg@comcast.com>,
> "pick one" <try again!> wrote:
>
>
>> Fords choice of tools has always been marginal. But by tapping into the coils
>> fuse with a low current probe ( all the coils share a common fuse ) you can
>> now
>> see all eight. If you know what cylinder is the suspect cylinder you can
>> easily
>> just use a low current probe on that one coil.
>
> To expand on this a little further, using a current probe on a
> Ford DIS or COP with multi-strike spark, one can actually
> determine whether the spark line was ever actually established
> inside the cylinder.
> Imagine, an E-350 with a V-10 and all you do to hook up is a
> fused jumper wire at the fuse box.
> Fast, easy and accurate.

But it's not "high tech"! That will just not do!

Bob

<relic896@hotmail.com> wrote in message
news:9mt421t6vi8vc0takq22g9bk3tu5gbjmgt@4ax.com...
>>Listen up Bozo; the shortcomings you possess are not necessarily
>>applied to the rest of the world (obviously).
>
> llmfao
> u go girl
> what shortcommings would that be ?
>
> hurc ast

The list is long and very obvious to anyone who has read at least one of
your posts.
Bob

aarcuda69062

In article <fJednZ8Tcac50b_fRVn-vg@comcast.com>,
"pick one" <try again!> wrote:

> "Jim Warman" <mechanic@tenalpsulet.net> wrote in message
> news:07rUd.7166$LN5.3763@edtnps90...
> > Most of the work arounds we come up with in the field are hardly high
> > tech.... though the thought processes to arrive at the solution certainly
> > can be. One tool I use more than ever, lately, is an old headlight with two
> > leads with alligator clips. The PC/ED instructs us to use a DMM to perform
> > tests where the DMM is an inappropriate tool overlooking the need to load
> > the circuit to get a true idea of it's condition.
> >
> > I'm sure we can all agree that selecting an appropriate test method to get
> > accurate results is more important than doing a "pretty" looking test. If we
> > fix the concern in a timely fashion without shotgunning parts, we've done
> > our jobs.
> >
> >
> That's for sure. One of the other problems is proper training. I can not
> remember a training class that taught the use of voltage drops. Use the term
> voltage drop to most and you get the deer in the headlamp look.

Because it's not "high tech."

(where did I hear that last?) 8-)

pick one

"Jim Warman" <mechanic@tenalpsulet.net> wrote in message
news:nDuUd.9894$hN1.4490@clgrps13...
> Everyone in the shop is constantly borrowing my "brick"... a scrap of
> construction 2X4 with a 2 post terminal strip and about 30 feet of paired
> wire... one red, one black, at the other end, two clips that fit on the
> battery terminals... colour coding is about as high tech as it gets (but I
> guess I could paint it, add some warning decals and a handle....). No more
> searching for a good ground or a convenient source of power.....
>
> Total cost using overpriced Radio Shack goodies.... under $10 CA..... Since
> electrical/electronic diag time is all MT, I haven't gained a thing (other
> than more time for good retail FR work) but my retail customers don't pay
> for me to fart around looking for a good ground.
>
> I wish I could claim the patent rights on this..... I read it somewhere a
> long time ago and did the old forehead flatten (with the required "DOH!!")
> since the idea was way to simple to think of....
>
>
That's the way it seems to always be. I got the idea of making a 20 foot test
lead by attending an electronics seminar a few years back. It was always a pain
to check the voltage drop of a ground in the back of a vehicle to the battery. A
lot of times it's not that you don't think of it, you do, but you question if it
is a good idea or not. One of my most borrowed "tools" is a led light I made for
checking hall effect switches, the other is a box of switches and a power supply
for checking trailer lights.