Hello everybody

I have 2012 s40 1.6 diesel and as I was driving home from work today I noticed that the engine temperature would go to red really quickly and after a few seconds go back down again. Also at that same time I stepped on the gas pedal to over take another car and my car didn't respond for a few seconds, it took a little bit before power kicked in and it started to accelerate.
My brother-in-law says that it is probably the thermostat and that it needs to be replaced.
I would like to see what you guys think and also if anyone can tell me where the rhermother is located.
I would like to do the job my self because money is tight right now but I need to prepare my self well wefore I take this on.

Thanks in advance

 

I would also.consider replacing the engine coolant temp sensor and the thermostat at the same time

 

Welcome to VF Darko

I can't find anything on it but this should be a picture of the housing. It may or may not have the thermostat built in. They don't sell the diesels here in America last time I checked and most of "us" on here are in the states so diesel info is in short supply.
Have you also checked you coolant level and condition. There is a possibility it could be a failing head gasket too.