Alfa Romeo Repair: alfa romeo 147 intermittent starting problem, alfa romeo 147, alfa romeo

Question
i have an alfa romeo 147 (02) 2.0 lusso the problem is when i start the car from cold its fine and runs ok if i switch it of and try to restart it wont i have had it on the computer and thefaults come up with
1. rpm sensor intermittent
2. temperature sensor intermittent
3. idle control intermittent
any ideas thanks
mike

Answer
First you must clean all grounds--not just the battery terminals, but, also, the ground connections on the engine and the body. Then, look at the plug connectors for the mentioned components--take them apart.  You will have to replace them even if they do not show obvious faults.  It could be that the reference signal is the actual culprit--but the whole connector needs to be changed.