Engine cut out and Lambda sensor

[jlawler]

In previous threads I had the prolonged diagnosis of a crank case position sensor problem followed by diagnosis of a leaking head gasket shortly thereafter.

So now the whole top end has been rebuilt and there is a new crank case position sensor and a new lambda sensor (as I gather the leaking coolent kills them). Both are OEM parts. The car has been running really well and I couldn't be happier.

Then just the other day the engine cut out. Wouldn't start but after waiting about a minute it ran again with no issues (luckily this was at the Supermarket car park). There was no spluttering just died so very much felt like an ignition problem.

Then today it did it again but the Lambda sensor came on first before the engine died and when I got it to restsart the Lambda sensor light stayed on. I pulled Fuse 1 and restarted it and the Lamda sensor light went out.

So any ideas on where I should start looking? I don't want this to happen in the middle of the motorway! I assume it's some ignition issue that is causing the engine to die but where to start and go about testing it?

I have a new crank case sensor and the old Lambda plus the control modules from a previous car.