Audi Repair: audi a4 1.8t auto, coolant temperature sensor, engine coolant temperature sensor

Question
hello,my son has a problem starting his car,after the car has been running .It has had a full service a cam belt replaced and a new ignition coil fitted,the car starts first thing in the morning but after driving for a while and stopping the car turns over but does not "FIRE UP"petrol must be there as it smells strongly of it the dash shows no faults any ideas !!!!!!!!!!!!!!! thanks

Answer
I think perhaps the engine coolant temperature sensor is bad, which gives the engine the wrong mixture when you attempt to start it.  Sound slike the ECT is stuck on cold reading, which is why it injects too much fuel stopping it from starting when hot.  Good luck,  Jan