Hi George.
Is the car diesel? It sounds just like water in the diesel fuel. If it is, there is normally a drain plug which will be shown in the car handbook that allows you to drain water out of the fuel line.
If it's petrol, there are obviously lots of things it could be, but you could try the common, cheapest remdies first:
1) Remove the sparkplugs and throughly clean the spring wahsers and the engine block where the plugs are seated.
2) Remove the distributor cap (at the other end of the HT Leads) and thoroughly clean inside, removing any 'crust' from the electrodes and also clean the rotor arm metal parts.
Neither of these will do any harm and it might just solve your problem.
I hope this helps.
Barry
November 2010
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