Testarossa 0.0% CO mystery - KE-Jetronic

Breakout box is completed and tested.
I hope the unshielded sections of cable won’t create interference for the RPM and TDC sensors.
Unfortunately I didn’t have enough hardware on hand to hook the 25 pins… so I can only use it for the microplex, I’ll have to update it to use it on the KE if needed…
Tonight, test session with a multimeter and an oscilloscope.
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Update after troubleshooting :
Non starting condition was solved after I found that I knocked the small round connector below the cooler tank while removing the distributor cap… But still on RH banc only.
Hooked the breakout box and all mesures came out pretty good…
Back to basics, last link that could go wrong was the ignition lead between the coil and the dist (I swapped the coils and modules before)…
Continuity check and a closer visual inspection revealed a corroded crimp connector on coil side.
Inner conductor of the wire turning to dust on the tip a very stiff insulation.
It seems that this cable end overheated making the core wire brittle and the insulation stiff.
Tried to shorten it an crimp the connector back but the protrusion that should penetrate the core wire was half gone?
Next mission is to find some wire and crimp connector…

I feel quite stupid for missing that but it’s 1st time for me that I experience such a failure.

 

Yes it’s a kind of “staple” crimp connection with a tab penetrating the cable core.
The tab itself seems to have broken into the cable.

 

Quick update,
Ignition is back, that was not so simple to find a correct ignition lead locally, had to go trough available reference at the local part store with an helpful seller.
I can confirm the poor construction of original Cavis with the pointed tab on the connector.
Locally sourced ferro-spiral leads have the connector with staple mentioned above.

Now a new problem, there's not enough fuel on left bank so I have to modify my breakout box for KE Jetronic purpose to rule out any issue with HEA driven by the ECU.
As the mixture screws have been fiddled before, I prefer to confirm that theres no electrical issue 1st before fiddling some more...
Tests 1 to 8 from diagnostic sheet N°6 were fine, I hope that there's no issue with the ECU and a proper setting of the mixture screw will solve the isse.

 

Thanks again everyone, the car is now running beautifully, my friend cannot be happier !

Sorry to Cavis for the misjudgement, been reading here and there bad things about those wires...

Before atempting to set the mixture, I checked all ECU parameters with my breakout box (that I had to repin).
All tests went OK, some were not that easy to conclude on the HEA current suppl behavor bu at least I made sure the KE-Jet was operating properly.

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The mixture was set at 1.0% CO on both banks for a bit of safety margin, left bank was smoking a bit and I thought plugs (and maybe valves) may be dirty with all that unproperly burnt fuel that went to this bank.
I then placed the new obturator scews on the setting ports as the original ones were damaged wile the tamper plug was removed.
Not easy to find new even through Mercedes but I randomly found a garage in France is making repro.

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I asked my friend to go for an Italian tune-up and I would come back to precisely adjust the mixture to original spec.

I was wondering if it would be worth it to set it a bit richer as the car has free flow Tubi Style mufflers (may woth checking on the dyno).