Using iPhone 4S in car for hands-free calling

I am having real trouble using my iPhone 4 S to make hands-free calls from the car. The combined earpiece and microphone I have always used without problem on my Nokia keeps getting silly results with Siri!

I just want to be able to make and receive calls using my Contacts List, and get Siri to recognise my voice when I ask for someone on the Contact list!

If I say I want to speak to 'Stephen Farley' it will come back with 'I don't see Stephen Bali in your contact list'!

Maybe I am doing something wrong?!

Also, will the 'voice regonition' work if Siri isn't working because it's out of contact with the internet?

I just need a simple connnection to my Contact List, without all the fancy options of Siri - which are just a pain!

Any help gratefully received!

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