Alarm imobaliser problem

Hi, can anyone help?

Discovery 1 300 Tdi, intermittent starting problem. Sometimes starts for days with no problems. Then won't start unles key in ignition and left hand fob button pressed. Sometimes have to lock and unlock doors, press fob buttons randomly, then it starts.
I've bypassed the spider. No difference.
Tried the key in door. Five left, one right etc. No difference
Unplugged ecu under passenger g/ box . No start
Can I bypass the imobaliser section of ecu? Orange and black wire?
Can I unplug everything and run cable from starter to ign switch?
Does anyone have any ideas? It's driving me mad..

Assume you central locking as the remote fob can loose its tuning in time, so an iffy fob will make it difficult to remobilise your engine, also "starting problem" u mean turning the engine over (cranking).
If the spider immobilise has be bypassed correctly there shouldn't be a immobiliser issue, you could move the fob nearer the ignition switch that does the same thing and would save you pressing the unlock button on the fob, no need to do that of course if the system has be bypassed.
No need to unplug anything, simply install a wire at the ignition switch wire where it enters into the fuse board to the starter motor solenoid.

Hi discool,
Thanks for your reply. I think the fob, fobs are both past there sell by, to be honest I use the key most of the time.
Spider definitely bypassed..
Fob hangs on key, so close to ignition.
Get in turn key, nothing, doesn't crank!
Pushy left fob button sometimes starts?
The red symbol Land Rover with something in the middle of it, is always on, when it won't start.
I thought that bypassing the spider, disarmed the immobiliser?? Mine is definitely bypassed and still imobalising..

Ok, my understanding it that the red LED shouldn't be illuminated, the symbol that is a car/key will illuminate only after there is a delay in starting the engine after the initial remobilising, i.e. when the vehicle is first unlocked.

The firm ReMote Key can refurbish your fob including installing an improved crystal inside.
So it appears the simples thing to do is install that wire and see if things improve, the wire that goes to the solenoid is coloured red/white at the fuse box I believe, the Haynes workshop manual wiring diagram will confirm the colour, or a volt meter showing 12v when cranking.

This was my understanding as well, but led is definitely on ! I am wondering if someone has had a go at this before me, and cut in to loom?? I've not had the vehicle long, and don't know it's history. Dash had been taken out before. In fact it he spider bypass had already been done. I did however replace the bypass with my plug, to ensure it had been done correctly..
I think I will try the wire !!
Thanks for your help