EA82T or mpfi coil wires - help needed

[steptoe]

so not to throw anyone, it is 3 plug ECU involved in 3/87 L series auto turbo

factory coil

KCM is Knock Control Module, mounted beside glovebox LHS

COIL POS+ terminal has three ring connectors on it

1. BLACK, red insulation on terminal crimp - goes to noise suppressor
2. BLACK/WHITE trace , black crimp insulation - TESTED to be IGN 12V+
is paired up with #1 below NEG (the TACHO) and enters wiring loom into LHS guard
3. BLACK/WHITE trace, red crimp insulation - goes to dizzy/knock sensor side of loom

got the positive side sorted I reckon

COIL NEG- terminal has four connectors, but five wires


1. YELLOW, black crimp insulation, loom wise is paired with BLACK/WHITE #2 above at POS
enters wiring loom and goes through LHS guard. If you have FSM 6-3 p5 shows it at connector F46
loomed with common ground D 6-3 p 20

>> EDIT>> Ah ha, got ya, this is the TACHO wire !!

2. YELLOW, yellow insulation on terminal crimp, loom wise is paired with BLACK/WHITE #3 above at POS
goes to dizzy/knock sensor loom >> dizzy/knock sensor side of black plug >>dizzy ignitor

3. This eye terminal has two wires connected, loom wise enters loom just below fusible links

[a] thicker wire WHITE that is then shielded in a GREY or WHITE insulation
this is the ignition pulse that goes to terminal 21 at ECU
thinner BLACK/WHITE [NOT TACHO I now know that much]



4. YELLOW, forgot crimp insul colour, goes to a white plastic connector like blinker lens and fuel pump connector, just below coil. Turns out this is the A/C amplifier wire


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Help is needed to identify NEG terminal #3 wire
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thanks heaps



What makes things hard is the Knock Control Module is not mentioned anywhere else in manual other than diagnostic pages BUT CORRECTION does feature in the fold out electrical diagram. It is missing from diagrams of connectors. Its location is kept secret and the wire loom is not featured nor its connectors (must be what we have to put up with when low grade fuel makes it neccesary)

[steptoe]

BUMP

OK, If I can ask one question at a time then...

anyone know wire at NEG side of coil 3 (b)? NEG side really only a signal side of things , after the switching is done, so how many signals does this beast need?

eye crimp terminal with black crimp insulation. Two wires on one terminal. About 50mm from coil is insulation tape covering the beginning of the shielded grey wire that encases the white wire that goes to ECU pin 21. The thin black wire with white trace - it is not tacho.Gotta say I do admire those of you who rip an ECU'd engine out of late models and shove em into MY and L's AND get them running correctly. I suppose practice helps



edited at 20 views

[discopotato03]

Trying to work this out from a copy of the efi section .

Pin 19 and 21 at the ECU get the shielded wire from the negative side of the coil (W) and 5 gets a (BR) control circuit ground .

Bingo found the diagram .

Hard to describe but

Shows yellow (Y) wire from coil (-) to the first of the four pins on the ignitor in the distributor .

The second pin on the ignitor (left to right) is wire coloured (BR) to the KCU .
At the KCU its labeled Ignition timing

The third pin (BW) coloured wire is IG Voltage at the KCU and is also connected to coil (+) .

The fourth pin (BY) coloured wire goes to Phase control signal at the KCU .


Now don't quote me on this but it looks like a (BW) coloured wire from the ignition relay powers up the positive side of the coil and via the other ganged (eyed) wires powers up the Ignitor and the KCU .

Silly me , sounds like you have a WSM . Look in the Fuel Injection system 2-7 on page 78 Fig 75 . The diagram shows the dizzy and connectors and what goes where .

A .

[steptoe]

YUP. Got WSM and that diagram and that BW wire goes to/from the POS(+) side of coil, whereas I am chasing a BW that connects at the NEG(-) terminal. FUJI ran short of coded wire and doubled up a few times here with BW. Nice try Adrian, effort is appreciated.

It looks to be that for ignition pulse connection to ECU on non turbo AUS it is pin 19 and AUS turbo uses 21 not both in one application.

[discopotato03]

The factory WSM Fuel Injection System section shows the ECU pin outs and the corresponding plug wire positions on P30 .
I suppose you could do worse than to pull the plugs on your computer and look for wires with the same colours as the one you're trying to trace .

Possibly another thing is to disconnect the unknown wire and see if anything doesn't work , provide it starts . If it did run you could check for trouble codes as well .

I know nothing about them but do USDM Ls have a speed warning device ?

Cheers A .

[steptoe]

thinking of sending a signal down from disconnected coil end and probe the ecu plugs to see if anything shows up, Have previously disconnected this termnal and sytarted and run the engine and had no ill effects, but remember the ecu is partly disconnected while on dedicated LPG. Plug 3 is the one further apart from the others and switches the fuel pump and injectors. Have pulled it out to deacivate the petrol side so running with the wire of topic disconnected likely not to have any effect unless I hook up petrol again.

If speed alerts were fitted to US models or other they would be more pulsed from speedo than coil ?