UK Car Repair: 1996 Vauxhall Astra Merit 1.4 hi t, vauxhall astra, coolant level

Question
1996 Vauxhall Astra Merit 1.4 hi t - for the last 2 months the engine will not start first time and sometimes takes up to five attempts before it will start. once started after driving about half a mile I usually have to stop at a roundabout and when stopped the engine is still running but when I try to move off in first gear as I begin to accelerate there is no power and cuts out. It then takes another 2 - 3 attemps to start it again by which time drivers behind me are getting frustrated and sounding the horn. The car is then usualy ok after engine warms up. But problem returns if it is left cold for a while. I took it to a mechanic two months ago who replace the plug leads, this made no difference and I then had the plugs replaced and this has not made any difference. One garage i went to tried to say it was the waterpump was about to go and it would cost £ 180 to fix but I am sure that it is not a waterpump problem ans its not overheating and the water level is fine. A friend sugested that it might be the automatic choke. Another mechanic couldnt find anything wrong with it. Please help, Im begining to lose confidence in mechanics altogether. Distressed Female!!!

Answer
Why anyone would replace the plugs and leads baffles me.  The problem is clearly in the cold start system. There is a temperature switch which controls this system it may be faulty. BUT, you need to take it to someone who can scan the cars computer to make sure that is the problem. Of course it is essential that the coolant level is full for the switch to work, but you say that the level is OK.