W124 E300D OM606 engine wiring harness

[SilverSaloon]

hi

I was aware of the common issue with the wiring harness on the petrol W124s, but I didnt realise that the E300D would also suffer the same fate, but it appears it has... i assume down to heat...

i am rebuilding the wiring loom where needed (a lot of it is solid it seems), but i have a question - the wiring that goes to the vaccuum unit on the underside of the manifold.... this has 2 connectors to it.... how is this wired?

there is a white/grey wire along with a brown (earth) wire that goes to the 1st plug

there is a yellow wire that goes to the 2nd plug along with the same brown (earth wire) as shown.

my question is, i am sure the yellow wire was wrapped/touching the white/grey wire - it looked twisted on purposefully, but isnt soldered, but hard to tell as all the plastic sleeve had disintegrated anyway.... should the yellow wire be completely seperate and only go to plug 2? i suspect so, as it makes sense, but would like a 2nd opinion on it before i reconnect it all up and heat-shrink the wiring.

does anyone know what bad connection like this would do when running?

here are some photos of the bad loom... it was bad at the manifold ends (as above), also the whole wire between the aircon compressor and the plug at the inner wing was degraded... so i've left it in situ but connected and run a new wire along to completely replace it; + and -.

 

[3 phase]

Derek, I can't help you answer your question, though I suspect the cables should be separate, someone will no doubt advise. My problem of intermittent rough idling I have yet to address, due to time and work commitments, but I will definitely be looking at my loom following your post and it will be interesting to read what effects the damaged wiring would have on the running characteristics.