Hi folks. I need some hints regarding a problem with my mum's Mondeo. It was left sitting for around 4-5 months. It's a 2000 Mk3 1.8LX that's done about 100k miles.

The battery was completely flat but the engine jump started quite easily. It seems to run fine, for a good 15mins or so at the most while not moving and the car can be crept forwards and backwards very slowly, but as soon as you try to drive it away there is a faint click and the engine dies.

A friend has suggested that the immobiliser may need reset. However I seem to recall that when the immobiliser is active, the car will not start at all. If it is the immobiliser how do you reset it anyway?

Any ideas will be appreciated. The car is not worth a lot so I want to avoid a mechanic if possible.

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