I've come across this on Vectras & Corsas before. It most likely is the idle air control valve - it tends to accumulate crud on the seat of the valve which prevents it from seating properly & this upsets the idle mixture causing it to stall.
Locate the idle air valve assembly & remove it (a haynes manual is handy for reference). Clean the valve assembly with carburetor cleaner or fuel injector cleaner ensuring all bits are clean. Squirt cleaner into the body of the injection unit where the valve has been removed to get it as clean as poss. Refit the whole lot & start up ! it's always worked for me.
Graeme
December 2005
Good news....and bad.
The good news is your are not the only one.
The bad news is that it happens to hundreds of poor hapless Vauxhall owners from Astras to Caviliers, at traffic lights and roundabouts.
It's probably a faulty idle control valve and will only get worse.
Best thing to do is get it fixed at a Vauxhall dealer than sell the car and buy a Jananese car. Go for a Honda. Put your time with Vauxhall down to experience. They are such cr*p cars. I know because I have one and it is forever stalling. The only thing sporty about it is its daft name. Astra 'Sport'. God I hate it.
Brian
August 2005
Automatic Answer
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