My poor 2010 Octy 1.6tdi has been sitting in the cold hardly run for months.  I've tried to keep the battery charged up. The engine will occasionally start, run for 1-2 seconds and then cut out. I've tried revving it, but it still cuts out straight away. If I switch off the ignition and try again it will do the same - start and then stop.

 

Any suggestions please?  Many thanks

Immobiliser not recognising the RF chip in the key.

 

Were you by any chance using a different key to the usual?

J.R. - thanks.  No, usual key.  I just wonder if the battery getting really flat has generally upset the electrics/computer side of things? When I open the door I notice the dashboard lights are not coming on that normally would.

 

Does the key fould when in the ignition. If so the transducer cannot see the key. Try to hold the base of the key in line with the blade when starting the car

 

Do these have a stop valve/solenoid? Could equally be that as much as the immobiliser. 

Thanks. No, the key does not fold when in the ignition and has never been a problem.

 

I wouldn't know about a stop valve / solenoid

 

Would disconnecting the battery help to reset the ecu if there is a problem there?

" When I open the door I notice the dashboard lights are not coming on that normally would. "

 

The immobiliser is held in the dash, so if it's not getting any power, the immobiliser will kick in after a couple of seconds.

 

Can only suggest you check all fuses including those in the engine bay fuse box. 

As suggestion above and check for corrosion around the engine bay fuses and fuseholders.

 

 

Thanks all.  It appears much simpler solution - despite charging the battery it clearly wasn't giving enough power to the ECU etc.  A new battery has sorted it, even bringing back to life the radio which had previously been asking for a code !

Ha - spoke to soon. Just went out and it is dead again. I give up . . .

Did you check for corrosion around engine bay fuses and connections as previous post? If not, you may have disturbed something to make a temporary good connection. Same applies to other wiring near the battery.

 

 

Get a VCDS scan done, if there is a power supply problem to the instrument cluster it will show up as a logged fault code, low voltage and/or failure to communicate.

 

If it is an immobiliser problem then the engine start with a non recognised key will be recorded as a fault code, I have been playing with a non chipped key so I can lock my keys in the car (long story & not relevant) the engine will start with said key and cut out in 2 seconds dead, the event was recorded as a fault code.

@J.R.

The key, no pun intended, is the 2 second running time.

 

Odd that VW would allow that if the car is set as immobilised, any car I've dealt with before that's been immobilised won't even crank.

 

Check the ground connection at the starter motor for corrosion.

Agreed, if it constantly and repeatedly dies after exactly 2 seconds I would bet my house on it being the immobiliser cutting in, the cause could be the key, the reader coil, a connection somewhere or more likely a dry joint on the instrument binnacle PCB where the connector joins it.

immobiliser kicking in, mine did the same when i pulled the fuse for the ESP, same fuse does the immobiliser.