Alfa Romeo Repair: engine fault, air flow meter, vacuum hose

Question
hi,i have an alfa 156 2 litre twinspark 1998...when i begin to drive off from starting the engine it is holding back and sometimes just dies..this happen hot or cold... i can start it up again with no trouble...also sometimes when i start it the revs of the engine stay at approx700rpm even when accelerator is down to the floor....also when driving it dos,nt seem to respond that well between 1000 rpm and 3000 rpm ..after 3000 rpm the engine goes like a rocket with no trouble..the engine has had a cam variator and timing done,,,a new air flow meter and a new intake pipe.to try and correct fault but with no luck...COULD YOU PLEASE HELP.I DON,T KNOW WHAT TO DO NEXT...thanks phil

Answer
In a situation like this there are two things I would check first: the map sensor operation and the throttle switch operation.  With the map sensor the first thing to check is that the vacuum hose is clear.  You need a digital multi-meter to do the other checks of the map and throttle sensors.
You need to check things before changing them as parts have become too expensive to not check first... Also, try cleaning the battery cables and while they are disconnected, touch them together for 10 to 20 seconds...