discovery 300tdi cutting out

will re start after few mins then sume times just wont start till u set alarm and re set it any advice will be a start is this a common problem

Ian, this does sound like a problem that has been mentioned here before and which I suffered when I had a 300tdi. There are potentially a few causes but the simplest one to check is the wire to the fuel cut-off solenoid, which is mounted on the distribution pump.

The solenoid is located at the rear of the pump (i.e. end closest to the bulkhead) and there is a single wire attached to it. The connection tends to become dirty over time causing the connection to be broken which, in turn,closes the solenoid and cuts off the fuel - it's how the engine stops when you turn off the ignition. The remedy is simply to pull off the connector and clean the male and female parts before putting them back together.

Im sure others will be along with details of other possible causes - and the alarm resetting suggests it could be the dreaded "spider" - but ths is by far the simplest to eliminate from your investigations.

HTH

but will re start after few mins then sume times just wont start till u set alarm and re set it any advice will be a start is this a common problem

I agree, we did a long europe trip a few years back in a 300tdi disco and had a similar problem. Eventually traced to a doddy connection on the shut off solenoid on the pump. try running a direct feed to it to find out whether its the feed to it, or the solenoid itself

Dave