matgriff

Active Member
Hi, 2 weeks into disco 2 ownership, I've been working through the car top to bottom, doing full service and looking at all the common issues.

I replaced the leaking cam cover gasket and cam seal last week. I checked the injector loom harness and it looked clean with no oil around it, in fact the loom cover was all crispy and brittle where it goes down over the inlet manifold, so i stripped it off and replaced it all... no signs of any oil or anything. Also the plug on the injector loom at the cylinder head looked clean.

Anyhow, today whilst finding a coolant leak, I decided to check the ECU, low and behold the red plug was full of engine oil, as was the female connector. Took a couple of cans of brake cleaner to get all the oil out. The connector was full of black crap.

Question is, when the injector loom seal leaks, does the oil get down the wiring loom outer or actually inside the wires between the insulation and conductor ? I have a recepit for "harness replacement" when I got the car, maybe they didn't clean the ECU connectors ?

I'll keep an eye on it and just replace it if it continues

Just interested

Thx
 
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From what I understand about this well known problem, and from what I've read the oil finds its way along the conductors inside the insulation by a capillary action.
It can apparently take a few goes to get it all clean again after replacing the injector loom.
Engine performance can become degraded probably because of electrical currents leaking across the various conductors not by the oil which is an insulator but by particles of contamination suspended in the oil, carbon and the like which might act as conductors.
 
OK thanks, I've ordered a new injector loom, I'll replace it later this week to make sure :)

I guess that's why you cant see any oil around the wires or in the outer loom, as it's actually inside the cores.
 
As Brian47 said, it will take a few cleans of the ECU plug(s) after changing the injector loom before you stop seeing oil in it. I've done mine 2 or 3 times in a couple of months and finally it seems dry.
 
Hi! Try not to use too much brake cleaner, it can attack plastics etc.
IPA or meths is good and wont attack plastics.
I used an old Aquavac to suck the oil out of the red plug.
Mark
 
Take ECU out and stand it up plug face down overnight on some paper towel. Remember and disconnect the battery first.
 
Replaced the injector loom and gaskets yesterday, there was no more oil in the ECU plug since I cleaned it last week... another job well done :)
 

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