What did you do to seal it? Is it a good idea to unhook the battery before removal?

 

in my case I had a quarter sized hole rusted through the fenderwell...strategically placed under the ecu....the corrosion was actually stuck to the ecu when i pulled it out. yes i would unhook the battery first, remove the ecu and unplug it...a lot of us here have had moisture inside.....just remove the screws and the covers, get it dried out....no solvents...a little wd40 is probably ok to use but dont leave it wet....use some rtv to seal it back up....even if this isnt your problem now....it good preventative maintenance

 

Thank you for that. I removed and cleaned, it was in surprisingly clean inside and dry. It ran fine afterwards, I'm not sure if was a coincidence or not.

 

Update: I ran my Disco in the dark with the hood open and poured water onto the ignition coils. I can see small arcing coming from beneath two of the spark plug boots onto the coils. I have dielectric grease on the wires and pressed them down down firmly. The wires are new kingsbourne 8mm wires and cheap spark plugs.
I have been searching, can I purchase individual coil packs? How do I remove them?
I can hear clicking with every flash of the arcing coil/wire.

 

There is a plug on the drivers side to unhook the set, then 4, 10mm nuts, studs may come out too then just snake them out sort of lift up and rotate forward? Iirc

I noticed last time I looked at plugs some actually mentioned heavy duty ceramic to prevent cracks and arc and compression loss

 

Your coils are leaking charge because there is a shorter path to ground through the boots than through the intended spark plug circuit. I might try the less expensive new plug/check the gap size route beore I started replacing expensive coils.

 

Did you ever figure out your problem? I ran through a puddle and same exact thing happened to me.

Thanks

 

Yes, the wirings heat wrap that runs to the crank sensor on the bell housing was corroded and allowed arcing when wet. I rewrapped the wires a few inches above the sensor and now the problem is solved.