Aygo Mk2 feels like its going to stall when braking

[Ixon1976]

Wonder if anybody can help before it's goes to the dealers, got this problem where the engine feels like it going to stall when I'm about to come to a stop its a manual btw, it doesn't do it all the time and no engine warning light neither and its not misfiring, also it seems to do it more when the engine warmed up. 

Could be a faulty o2 sensor or the idle control valve playing up?.

[TonyHSD]

Hi, 

what is the mileage on this car? 
I believe the throttle body regulates the rpm and there is no idle control valve on these engines and if so then a dirty throttle body can be the reason. 
When you have dirty body often the symptoms are exactly as yours and happens only on warmed up engine and when weather is hot. Most of the times there are no faults detected or stored in the ecu. 
Another reason for low rpm can be use of AC and this will load the engine and make it feel like it will stall. In addition to all above a low 12v Battery can add up to the low rpm picture, everything actually that is run by the engine crankshaft. These are things to check. Diy, local mechanic or dealer garage it’s your choice. 
Good luck 

[Ixon1976]

It's a 71 plate it's now booked in with the dealers for the 8th of next month, it definitely not the AC kicking in. Could be the Battery it's now over 3 years old.