I have just had this problem, I have fixed it as follows.
1. Cleaned out the air box, new air filter - still won't idle
2. Checked all the inlet hoses, found a split, repaired that - still won't idle
3. Replaced all the vacuum lines, started hunting at idle
4. Adjusted the mixture using the air screw at throttle body and adjusted the mixture screw in the air box - idles perfectly when warm, stalls when cold.
5. Checked out the three senders on the right hand side of the block, 1 feeds the temp guage, 1 feeds the ECU and the other feeds the Idle speed control valve, two of mine were faulty £10 fix from GSF, idles perfectly now.
Hope that helps you.