Re: Immobiliser problems
I had a similar problem on my 156 - code light stayed on meaning the car would turn-over but wouldn't fire. Persevering with turning it on, leaving it for a while then trying, fixed it and my problem was intermitent so let it go for about a year before it finally gave up properly (strangely it didn't get more frequent or anything it just played-up one day and simply wouldn't start).
It needed a new ignition ECU which was about £300 if memory serves.
Another sympton with this would be the airbag warning light staying on as the ignition ECU is connected to this.