Hi, can anyone help?

'99 Octavia 1.8T Estate

Intermitant problem with Central Locking and immobiliser.

Sometimes the yellow 'key' symbol in the dash is flashing when the ignition is turned on and if I try to start the engine it runs for about 2 seconds then dies.

Also, (connected I think) when locking the car the N/S/R door does not lock, (I notice that the red LED is not flashing in the drivers door panel) if I press the 'lock' button on the remote key again (generally at the third attempt) the LED will flash and the N/S/R door locks.

Occasionally engine will run really rough at low rpm (no pull) when this has cleared after say half a mile, the idle fluctuates up and down (2000rpm ish).

Sometimes a warm engine will not restart but I have found that if I floor the throttle it will eventually start, followed by rough running and a horrible smell.

There's more...

Airbag warning light on. (unrelated I think, but read on)

I've replaced the coil packs (improvement)

and the temp sensors (improvement)

Now, this is where I think the problem may lie.

The Climate Control drain pipe got blocked and water was sloshing about in the baulkhead and eventually found its way out down the N/S 'A' post and into the N/S/F footwell. (WAY back, whilst under warranty my local dealer replaced the door seal twice), well, the C/C drain pipe got blocked again recently and on further investigation I found that it was also dripping water onto the 'electrical control box' mounted under the centre of the dashboard.

So, my question is... What does this 'box' control?

I think I have two problems.

I need a N/S/R door actuator but the rest could be down to the 'box' under the dash

Bump

I think the door issues are related to water ingress to the convenience module in the driver's door. Certainly it would be worth checking that and cleaning the contacts before spending out on a door actuator.