Right an update. I went in to the garage again today to ask if I could get the car to my workshop. They said that they didn't want to give me a headache so took it to Vauxhall yesterday. BANGS HEAD!

I got a phone call this afternoon to say that Vauxhall had taken a look at it and the oil pressure switch had failed. It had leaked oil through the switch up the wiring loom to the ECU this has damaged the ECU which will need to be replaced. Also the wiring loom needs to be changed at a cost of a grand for the loom.

The main dealer said this is the third one this week they have seen. So just a heads up to others.

Thanks for the offer of help Mark, much appreciated. Also thanks to the others for your input. My gut feeling was an ECU fault but it was getting it back to my workshop to prove it.