Thread: Completely and utterly flabbergasted

Dear Enthusiasts.
On Saturday we decided to give our more or less stock standard Disco II, TD5, 2004 model a major service.
I started draining coolant, replaced all water hoses, fan belt and tensioners, Camshaft cover gasket, etc. I then progressed changing the oils (Engine, diffs, transfer case), both oil filters, fuel filter. We also removed the EGR-unit and replaced it with a much neater free-flowing pipe. We removed the solenoids and blocked off the vacuumtubes.
We started the car and found a exhaust leak on the blanking washer that came with the kit. We made up a copper washer and all went well. I've got a Rovacraft diagnostic tool and it didn't show any logged DTC's.
Sorry for the long introduction but I think it might become important.
Then we progressed doing the auto gearbox oil change. First we drained the oil (It was rather black and off but not unusual in appearance). Once I pumped in the fresh ATF until it was overflowing we then lowered the hoist, started the car, went through the gears and left the car running. We brought the car back up whilst it ws idling and continued filling the gearbox until it just started overflowing.
But then, all at a sudden, the engine made a bit of a rumble (Like running on choke) and then stalled. Hmmm, that was unusual. Lowered the car, tried to start it: It cranked but won't fire! After the third attempt, all at a sudden, the hazard lights came on and stayed on without pushing a button.
Ahaa! I thought this was related to the inertia switch (They are a bit dicky). Removed the inertia switch, checked and cleaned contacts, even bridged the switch but same result: Cranking but no firing, although it gave us the impression it was about to fire. As we replaced the fuel filter that morning, I thought it might have been air in the system. So, we went through the cycling process (5 times throttle down)(Multiple times). Still no result. Maybe there was something wrong with the new filter, so we put the old filter back in place but same result.
Maybe the fuel pump had died? Well we could hear it running and there was pressure (Holding the thumb on the drainhole of the fuelfilter). I even compared it with an other identical and functioning discovery; same result.
So: Inertia switch OK, Fuel pump and filter OK.
We decided then to try some Start-You-Bastard spray. During cranking it fired up briefly. So, it seems there is no fuel going into the combustion chambers. I have to remind you the car was perfectly fine until we started replacing the oil in the auto gearbox.
The battery became weak and also the M+S lights started flashing, so we pulled out a new 900 CCA battery from the other Discovery, still same result.
I was running out of options now. Could it be the notorious XYZ-gearbox switch? Removed it, opened it up, cleaned it, checked all tracks on continuity, etc, put it back together but same result.
So, when we are going through the gears: P, R, N are all good but the moment we hit Drive or the lower gears it only shows a flashing "D".
Maybe there was no communication between BCU and auto gearbox. So, we locked the doors by plip, opened the doors by key multiple times. During the process sometimes the car alarm went off but could be silenced by the plip. We then disconnected the battery for more then an hour (Whilst we were surfing the Land Rover forums for more ideas). Still no improvement.
We backtraced every possibility of the stuff we had done so far and replaced the new parts with the old parts again, but still no result.
We also swapped identical relais around, checked all fuses for continuity.
My diagnostic tool hasn't shown no DTC's logged in the ECM, BCU nor SLABS. After two days of trying every scenario we are coming to the point where we need some advice.
By the way, the fuel pump has been replaced a couple of months ago.
How is it possible that during changing the gearbox oil all at a sudden the engine dies and won't start again???
We are truely puzzled and every bit of advice is very welcome. Many thanks in advance.

i do not know the D2 auto.

but how much oil did you put in it??? you state untill overflowing??