Oil in ECU

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Nickeb

New Member
Posts
2
Location
Devon
So I have a discovery and the engine was running poorly with the flashing M & S lights - so I changed the loom etc cleaned out the ECU plug. It was good for 50 miles and then started misfiring again - the D light on the dashboard would go out - then might change to 3 whilst driving etc etc. So I cleaned the ECU out again and it was fine for a while and then the same happened again more oil in ECU - not engaging in Drive properly. there is still oil getting into ECU plug - what am I missing?
 
I presume that you're referring to the injector loom and oil in the red plug on the engine ECU.
First of all, take a look at this:-

http://www.discovery2.co.uk/Injector_harness.html

Any oil contamination must be allowed to drain out of the wire loom between the engine and the ECU. It can take a while to accomplish. The wiring will often look clean - on the outside but the oil actually runs along the metal of the wires, inside the insulation.
You might have to open the ECU to clean out any contamination that might have found its way in too.
The quality of the replacement injector harness which you fitted could also be the cause of your recurring problem.
 
Thanks - do you think that if I didn't clean the wires properly or the hole where the O rings sit that could cause the issues? Is it a matter of time or do I need to take the head off again and give it a better clean
 
As I said, the problem is the oil running down along the metal of the wires inside the insulation. The hole through which the connector fits has "o" ring seals which should seal, but even when it does it probably still wouldn't prevent the oil making its way down the loom to the red plug.
The oil will drip out under its own steam and gravity so it will mean that you will have to clean the red plug a few times after replacing the injector harness. you should also remove the white insert to clean out the inside of the red plug especially in the case of serious contamination.
I've not heard of any way to stop it once it starts, other than to replace the injector loom and take time to let the oil clear out on its own.
 
You can try removing the ECU (remember and disconnect the battery first) and stand it on a paper towel, plug side down, over night. You will be surprised how much oil comes out it. I was a bit reluctant to open mine up as I have an elephants touch. This worked for me but had to do it over two or three nights.
 
As meego says ,, I also squirted wd40 into the socket before i left it overnight ,, I then used tissue threaded between the wires just before the plug ..if you can try to make the wires run slightly up just before the ecu ..
 
Get some aerosol brake cleaner, that really works a treat but use washing up gloves or similar as its pretty terrible stuff to go onto bare skin!
 
Get some aerosol brake cleaner, that really works a treat but use washing up gloves or similar as its pretty terrible stuff to go onto bare skin!

Any solvent which doesn't leave a residue or attack plastic should work. I tend to reach for a spray can of Iso Propyl Alcohol (IPA) or 1:1:1 Stabilised Trichloroethane (NOT trichloroethylene) often called "residue free switch cleaner", a small paint brush might also help to get into the corners.
You can remove the white insert from the plug to clean inside there too.
 
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