My octavia vrs keeps stalling when i try to start it occasionally :-( is there any way or any place that can test if it's the key wire or ecu????

Do you get the flashing key symbol on the dash, if you don't then the cause is elsewhere and not immo related.

 

A scan with VCDS will show what is actually causing the engine to stall.

Had scan... Told me engine cut by immobiliser and light flashes on dash when stalling... But it's not every start?

Just don't want to pay for new key if it's the lead or ecu

The key is a simple transponder chip so unlikely to be the cause, I am not to sure where the transponder coil is on the MK1 Octavia but it would be the first thing to check.

What is to check? Can it be replaced

Do you have any other car keys on your keys?

No

I read somewhere that a weak battery might cause immobiliser problems,something to do with not producing high enough voltage.