Tach wiring, what colours?

i’ll preface this by saying that i’m an xjs owner.

i’ve bought a 4 litre aj6 with getrag 290 and have put it into my 3.6 auto xjs.

its running and driving, however my tachometer and speedo are not working. can anyone verify what colour wires come out of the ignition coil?

i’ve essentially spliced a 4.0 loom into a 3.6 loom. and don’t think i’ve got everything connected properly yet. any help or even diagrams much appreciated!

Now this is just speculation but I think on the XJ40 the tach may get the info from the CPS/ ECU and the speedo is run from a sensor in the rear hub …maybe wrong but that’s how I thought it went …others will no doubt know for sure …

Right as usual Larry. Pin 11 in the yellow connector at the ECM / ECU. A purple / yellow wire that is spliced to a red / yellow wire provides the engine speed signal to the tach. Or that’s how I’m reading the wiring diagrams in publication S6593, the 1993 electrical guide.(Figs 12 and 30).

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