Vauxhall Astra cutting out when slowing down

my car keeps going to cut out when i come to a halt at lights etc , if i apply power the car wont cut out but will repeat this process until it does cut out or i turn engine off , ive had new egr valve , coolant sensor fitted and have had the throttle body and iac cleaned and the problem still exists, i did notice that if the temp guage works correctly and the engine is at correct temp there was no problem with car and it drives spot on but recently it has been doing it regardless of temp guage working , when the car isnt doing this it drives lovely with no problems , any help or comments would be much appreciated .