EDIS module issues

[Random Hero]

Heyas, I'm running an MS2 SMD board on a customer's 280z fitted with the EDIS 6. We have had a bit of trouble with the system and I need some advice on where to go next.

Our first setup we bought used from Boost Engineering. $100 for the setup so it couldn't really be beat.

We had some intermittent tach signal issues, and came to found out that at idle the EDIS would simply skip a beat at idle and not fire at all, this of course led to tach signal drop out, but the engine would stay running. We narrowed the problem down to the module, and contacted Boost Engineering. They were super cool about it and sent out another module no questions asked. We got the other module in and the car ran great. I started tuning on it and we got to the point where we had good idle, cruise and I got the VE table dialed in almost to redline (going to save that part for the dyno).

Trying out some 3rd gear pulls the tach signal will now completely drop out from about 3300 to 0 in about half a second, then return to normal. So I figure, ok, no big. gie we'll get another module since a different module fixed it last time. This time we'll get it new from a dealer to make sure we get a hold of a good one.

I have tried 2 different modules from dealers and any time a different one is connected the engine will not rev past 1500, it will just miss and bounce back down to almost 0. While connected to MS and looking at it with a timing light I can see that it is not running in limp mode as the timing runs 16 deg. at idle, but there is no advance at all when you try to rev the engine.

My question is this, aren't these EDIS modules supposed to be interchangeable? We have been sure to order the EDIS 6 module, I just find it hard to believe that I have gotten 2 bad right out of the box. Is there some kind of difference between some of the pins? I know there are many different part numbers for the modules, but any one we have ever had has been a motorcraft part.

[Heribert]

A module can of course have intermittent fault but IMHO EDISis about as good as stuff gets.
Some ideas:
EDIS ( at least the ones I have bench tested) are sensitive to spark circuit ( ie plugs and leads) resistance. There is some kind of circuitry on the coil driver side that diagnoses if spark over voltage at the HT side is irregular. This can lead to module shut down that requires power cycling. It can happen if the spark circuit on each tower has less than 5 kOhms in total ( plug and lead in series)
It is probably a feature that also sends out error codes on pin2 so an original FORD install can read that and light up the dreaded " Check Engine " lamp.
So by all mans , make it your first priority to use resistor plugs and/or resistor wire.
I use NGK "R" plugs and that works great with copper HT wires

Some guys have had EDISproblems due to weak mounting of the EDIS VR pickup and or non-screened VR cable

To try , disconnect the SAWsignal from MS to EDIS ( SAW is pin 3) and see what happens then. With a correctly phased VR sensor( check the manual) the engine will run at 10 BTDC at revs over say 200 and stay there at all higher revs

Several faulty EDIS modules in one install seems quite unlikely.

Heribert

[trakkies]

Any simple way to check the EDIS module other than by substitution? For example, will it still produce the PIP signal with the coils unplugged - or with no plugs connected to them?

[Heribert]

I really do not know. I guess there are differences between some EDIS modules in the way abnormal spark circuits affect the error codes and the PIP signal, but I have no facts on this of a general nature. But I HAVE tried benchtesting an EDIS 8 with copper HTwires and zerRplugs. Sparking would cease, as would PIP signal in about 20 secs after start.
An EDIS 6 module behaved the same.

With original EDIS HT coils, a 20µF cap on each +feed to the coils and a correctly installed VR sensor , the one culprit remaining is the wiring to the module.
Some guys have managed to swap the 1-12 backwards. After correction all was well.
So one faulty EDISmodule is possible, two hardly so and three in a row is no way!

Heribert

[Random Hero]

Any simple way to check the EDIS module other than by substitution? For example, will it still produce the PIP signal with the coils unplugged - or with no plugs connected to them?

Only way I know of is stated in the EDIS documentation at megamanual, by disconnecting the SAW signal from the MS and letting the EDIS system run in limp mode where it should run 10 degrees across the board. I just don't understand the problem I've had with most of these modules. I have played with the sensor to wheel gap, adjusted rpm trim pots on the board and played with the next pulse tolerance in the software. I got the 2nd module to run correctly by adjusting the sensor gap a bit closer, but the other modules still cease to fire at certain rpm points with the same setup.

Pretty much all the part numbers listed in the documentation will get you the same motorcraft part from the dealer, only thing I can figure is that maybe there is a difference in specification of the sensor to wheel gap for different year models.

[Heribert]

and


Random Hero.

You write Q I have played with the sensor to wheel gap, adjusted rpm trim pots on the board and played with the next pulse tolerance in the software. I got the 2nd module to run correctly by adjusting the sensor gap a bit closer, but the other modules still cease to fire at certain rpm points with the same setup.UQ

This doers not make sense to me, at all. EDIS is a standalone system that makes great job out of converting a 36-1 wheel read by a VR sensor to a rock steady RPM signal on a 12V pulse train (PIP) into the MS. Run it to the optocoupler input. There is no need whatsoever to condition, tweak or fudge it in hardware or software. Set the firmware to EDIS ,keep track of rising or falling to get the SAW correctly phased ( depending if you sink or source current thru the optocoupler).
On installs with a dia 250 mm wheel, abt 4 mm wide and square cutouts with a 50% cutout I have tried several engines with VR to tooth gaps from 0,5 mm to 3 mm
and never missed a beat.

Best regards

Heribert