:idea:this happened with my panda 1.2 dynamic. it was simply the key. If you have a spare try that. when they get old they need to have something done to them to activate them again. the fiat garage couldn't argue as eventually one key failed to even start the engine whereas the spare still worked. i had TO BUY A NEW KEY AND SPARE AS THEY DIDN'T HAVE THE NUMBER TO REPROGRAM IT AS I RECALL.
THE CAR WOULD JUST DIE AND IT WOULD BECOME VERY HEAVY. IF I PULLED OVER AND THEN STARTED IT UP AGAIN IT WOULD RUN ON AS IF NOTHING HAD HAPPENED. IF YOU HAVE A SPARE KEY SUGGEST YOU TRY THAT AND SEE IF THAT MAKES A DIFFERENCE BEFORE GOING INTO THE MORE TECHNICAL STUFF. i PAID FOR A DIAGNOSTIC THAT COST £58 AND WAS A COMPLETE WASTE OF MONEY AS THEY TOLD ME WORK NEEDED DOING THAT DIDN'T GRRR :idea:
I'm sorry but this is complete cow excrement, at least in relation to the Stilo - although probably many vehicles besides too.
The immobiliser system works on the detection of a small immobiliser chip within the key, which is detected via an antenna built into the ignition barrel of the car.
There is no servicing, no activation, no reprogramming needed for any of your existing keys. Once the key is programmed to the car, from factory, it's done for life. That is unless you decide to reprogram the car and remove the key - in which case the key is blocked for life by the car.
Not having the "number" to reprogram is also poop too. You need to have the security code for the vehicle in order to be able access the immobiliser unit on the car to program it, regardless of whether you program a new key or are working on an old one. All codes are held by Retainer Group in the UK and all dealers are able to access codes from them electronically for a small fee.
You will know if your car is immobilising itself as you'll get an appropriate warning on the dash, such as an amber key signal or "CODE" message (sorry I can't remember the exact indicator for the Stilo off top of my head right now).
Back to the OP's issue... For the JTD I would suspect a fuel supply issue. So check the fuel filter. You might wish to use the drain on it to check that there is no water in the filter, as this can cause issues. You should get an amber warning on the dash for this but not always.
Also check the fuel pump relay - I suggest swapping it with a different relay just to check (they're not expensive if you wanted to buy new just to rule it out). I've first hand experience of a fuel pump relay failing and the car would cut out at random and restart again on the key as if nothing was wrong. You could temporarily 'hot wire' the relay to test it too.
