Random high RPM when slowing down/standing still red light (Volvo V50 1.8 Flexifuel 2008 Manuel)

[rancid sand]

Hi,

So I have this issue with my car where the rpm stays at like 2000 when I slow down, which is unusual because all my manual cars before this car never had this issue.

Example scenario:
I drive 60 km/h at 4th or 5th gear so normally the rpm will be around 2500, I then decide to slow down the car because there is a red light in front of me, ones I decide to slow down and press on the clutch pedal the rpm goes down to around 2000 and stays there even when I reach the red light and full stop. It remains 2000 rpm for like 1-2 seconds then goes down to the normal levels of 1000-12000.

Random high RPM when slowing down/standing still red light (Volvo V50 1.8 Flexifuel 2008 Manuel)

[meager granite]

Not sure about that car but it kinda sounds like a vacuum leak

[rancid sand]

Interesting

I will look into that

[rancid sand]

Is there a safe way to look for vacuum leak lol

[meager granite]

Safest way is smoke machine

The not so safe way is spraying flammable shit in your engine bay and listening for the engine to rev

[rancid sand]

Is it not bad for the engine to fill it up with smoke?

Cuz I found some dude that made his homemade smoke machine for 15$, and im planning to create one myself

[meager granite]

No it's a different kind of smoke

[rancid sand]

So I shouldnt use the DIY smoke machine thingy ?

like this dude:
https://www.youtube.com/watch?v=Ai6QkF2Ez3A

[meager granite]

Baby oil won't harm anything