Disco 2 Injector rail replacement, but not the harness?

Having has a few issues, and finding a small amount of oil in the red plug (only), I’m swapping the rail out this weekend.

I can’t seem to find any info of people changing the whole harness though, shouldn’t it be done st the same time as the oil will still be in cables/insulation? I understand the root cause will have been resolved, but shouldn’t it be changed as a matter of course?

Are there no issues once the rail has been replaced?

Billy110 said:

Having has a few issues, and finding a small amount of oil in the red plug (only), I’m swapping the rail out this weekend.

I can’t seem to find any info of people changing the whole harness though, shouldn’t it be done st the same time as the oil will still be in cables/insulation? I understand the root cause will have been resolved, but shouldn’t it be changed as a matter of course?

Are there no issues once the rail has been replaced?

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Generally the "Injector loom" is the part that wires the injectors to the plug and socket arrangement at the front of the cylinder head.

You're right to suspect that there's oil in the harness between the ECU and the engine, but normally there's no need to change that. However, it's usually necessary to let that small quantity to drain out. It could take a couple of tries to get it all out.

You should also check the red plug carefully by taking the white insert out and washing out the oil in there too. Most members use something like brake cleaner fluid or IPA. Don't use the type of switch cleaner that leaves a residue, and check that your cleaning fluid isn't going to damage the plastic of the plug and insert.

This guy has done a pretty good write-up on replacing the injector harness; a lot of members who have done the job have used his web page for guidance.

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

Thanks Brian,

Yes, I’ve found his site a massively helpful resource.

White insert out last night and only a small amount of oil found. Until I removed the insert, I didn’t think there was any, I think I have caught it just in time.

Be warned, you might have to check the red plug a few times in the future as the oil drains out.
Just out of interest, the oil contamination actually runs along the copper wires inside the insulation by capilary action, so you're unlikely to see it until it raises its ugly head at the red plug.
Generally clean engine oil is an insulator, but used or old oil which as you've probably noticed is black in colour contains carbon deposits and it's the carbon that screws things up.