My mk3 key into mk4 fob

[northeast_gti-t]

As per title seen this how to http://www.pocketrocket.ca/switchblade_key.html
and like the idea of having the mk4 fob albeit with non working buttons 
So the key i have with mine looks like a non original key as theres no vw emblem? mine says italy one side and the other side HU49T1 theres a small hole above the blade i notice and at the rear a red chip like cover (but thats near where the key ring fit is) So as its on the curved bit surely theres not a chip there for immobiliser?
my car is also fitted with a cobra full closure cat 1 alarm/immobiliser  with a key for overide i presume
the item i'm looking at http://www.ebay.co.uk/itm/161033084485?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1497.l2649 my question is as my cobra system has the remote etc will i need to use the immob chip from the key (if it has one) somehow get that fitted into the mk4 fob or is the immobiliser disarmed when i unlock the door and put the key in the ignition (if i dont start the car within a 30 sec period i have to press the unlock on the cobra remote to start the car)

sorry for the long winded post  trying to relay as much info as possible...

[gasketface]

You can tell if your car has a factory immobiliser by looking at your ignition switch.If it has a black ring around it then it has one,no black ring = no immobiliser fitted as standard.Behind your ignition cowling there is a chip/key reader if you have an immobiliser,unlocking your door does not turn it off.Removing the chip from your old key can be risky as they shatter very easily and are glued in.Some key cutting places will do you a new programmed chip for around £25 all in.Good luck.

[boneybradley]

your immobiliser key will be under the red bit as my spare is the same, luckily that makes it easier to remove and fit into a new key (or I guess get another chip from timpsons etc)

[northeast_gti-t]

You can tell if your car has a factory immobiliser by looking at your ignition switch.If it has a black ring around it then it has one,no black ring = no immobiliser fitted as standard.Behind your ignition cowling there is a chip/key reader if you have an immobiliser,unlocking your door does not turn it off.Removing the chip from your old key can be risky as they shatter very easily and are glued in.Some key cutting places will do you a new programmed chip for around £25 all in.Good luck.

Yep has the factory immobiliser,thanks for your info

[northeast_gti-t]

your immobiliser key will be under the red bit as my spare is the same, luckily that makes it easier to remove and fit into a new key (or I guess get another chip from timpsons etc)

cheers mk4 fob arrived yesterday and as you say chip is under the red bit i pushed the tray out via a paperclip i shall fit this into the mk4 fob also  job for today i think