Fordnatics List Archive

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Mail From: (email redacted) (Matt Silveira x257)

Greetings once again, all:


Well, after many days of arduous testing and some visits to the dealer
I have more information to share.


When I took my truck in for an unrealted oil leak(s): rear main and
transmission case, I complained to the dealer about pinging in hot
weather conditions. The service manager laughed and showed me a small
electrical connector (kind of like a black Molex connector) and haned
me a small plug for it. He explained that this will "bypass" some part
of the computer system and advance the timing and *very* slightly
enrichen the EFI. Hmmm......

I was VERY SKEPTICAL but I plugged in the thing and on the way back to
work (over 98 Deg. F) that day, the truck ran like. . . . well, let's
say that I am thrilled.


Does anyone know what this little plug is supposed to do?!? For a
reference point in the engine compartment, it is near the starter relay
by the central fuse block. It only has two wires leading to the
connector.

Also, the reason the truck was at the dealership is that it is a 1993
model and already sprung a leak at the rear main and the tranmission
case (5 spd.) between the main case and the tail cone. The same
service manager said that 4.0's have a problem with leaks. But if this
is the case then why not recall?

This read-only message was archived from a public mail list.
Mail From: Kevin Martinez <(email redacted)>

On Fri, 8 Jul 1994, Matt Silveira x257 wrote:

>
> When I took my truck in for an unrealted oil leak(s): rear main and
> transmission case, I complained to the dealer about pinging in hot
> weather conditions. The service manager laughed and showed me a small
> electrical connector (kind of like a black Molex connector) and haned
> me a small plug for it. He explained that this will "bypass" some part
> of the computer system and advance the timing and *very* slightly
> enrichen the EFI. Hmmm......
>
> I was VERY SKEPTICAL but I plugged in the thing and on the way back to
> work (over 98 Deg. F) that day, the truck ran like. . . . well, let's
> say that I am thrilled.
>
> Does anyone know what this little plug is supposed to do?!? For a
> reference point in the engine compartment, it is near the starter relay
> by the central fuse block. It only has two wires leading to the
> connector.
>

Sounds like the plug that you insert when you are setting the timing on
the engine. This prevents the EEC from adjusting the timing as you try to
set it to the factory specs (an annoying experience to say the least!).

If this is the case and running with the plug inserted makes the engine
run better, it sounds like the EEC microcode needs some work. Has anyone
seen a Ford TSB that mentions this?

Kevin Martinez
(email redacted)

This read-only message was archived from a public mail list.
Mail From: (email redacted) (Scott Griffith, Sun Microsystems Lumpyware)

On Jul 8, Kevin Martinez wrote:

> On Fri, 8 Jul 1994, Matt Silveira x257 wrote:
>
> > When I took my truck in for an unrealted oil leak(s): rear main and
> > transmission case, I complained to the dealer about pinging in hot
> > weather conditions. The service manager laughed and showed me a small
> > electrical connector (kind of like a black Molex connector) and haned
> > me a small plug for it. He explained that this will "bypass" some part
> > of the computer system and advance the timing and *very* slightly
> > enrichen the EFI. Hmmm......
> >
> > I was VERY SKEPTICAL but I plugged in the thing and on the way back to
> > work (over 98 Deg. F) that day, the truck ran like. . . . well, let's
> > say that I am thrilled.
> >
> > Does anyone know what this little plug is supposed to do?!? For a
> > reference point in the engine compartment, it is near the starter relay
> > by the central fuse block. It only has two wires leading to the
> > connector.
>
> Sounds like the plug that you insert when you are setting the timing on
> the engine. This prevents the EEC from adjusting the timing as you try to
> set it to the factory specs (an annoying experience to say the least!).
>
> If this is the case and running with the plug inserted makes the engine
> run better, it sounds like the EEC microcode needs some work. Has anyone
> seen a Ford TSB that mentions this?

Actually, it's the other way around. That's called the SPOUT
connector, and it is used to provide a feedback path from the EEC-IV
to the TFI module on the distributor to control the timing. If the
plug is _out_, it interrupts this feedback, and the motor falls back
into running with base timing only (as set by the distributor's static
setting), and no adaptive advance control.

If the SPOUT connector isn't there, you'll be running with the base 10
degrees advance, across the rev, load, and temperature range. I would
not be at all surprised to hear that the truck ran like hammered
dogmeat in this mode! When inserted in the socket, that little
connector allows the EEC-IV to give you the other oh, 20 or 30deg
advance you might need now and again for power. And the handful of
degrees retard that you might also need to avoid spark knock in the
hot, part-load operation. I imagine the improvement was _sizeable_.

EEC-IV controlled motors simply work like crap without that connector
installed. Its only function is to allow you to force the spark to sit
right at base timing with no adaptive advance or retard, so you can
initially set up the timing with a light (otherwise, the timing will
dance around as the EEC-IV adaptively controls the idle in real time).

Someone was a bit careless in a tuneup, or maybe in dealer prep, and
left it out. It must have been a real handful. I imagine that you'll
find all sorts of fun error codes if you run the self tests!

-skod

- --
Scott Griffith, Sun Microsystems Lumpyware
expatriate SCCA New England Region Flagging/Communications worker
(and driver, of anything that turns both right and left,
and can pass tech...) Return Path : (email redacted)