[Agsvg]

I just bought a r53 and things were good until recently. Firstly the idle is high, sitting at around 1200 and it likes to climb to 1600-1800 before dropping back down to around 1200 and it does this none stop,(every few seconds) the only thing that stops it, is when it's in gear, also the car feels down on power. Any ideas on what that could be?

 

[mike1967]

I just bought a r53 and things were good until recently. Firstly the idle is high, sitting at around 1200 and it likes to climb to 1600-1800 before dropping back down to around 1200 and it does this none stop,(every few seconds) the only thing that stops it, is when it's in gear, also the car feels down on power. Any ideas on what that could be?

without a diagnostics scan its all guess work and thats the mother of all things wrong,
smoke test the inlet pipes, maybe throttle body fault, maybe diver tor valve on super charger faulty, coolant tmp sensor another maybe, but like said all just guessing and better to have car scanned and no whats wrong rather that guessing

 

[gummysergeant]

I just bought a r53 and things were good until recently. Firstly the idle is high, sitting at around 1200 and it likes to climb to 1600-1800 before dropping back down to around 1200 and it does this none stop,(every few seconds) the only thing that stops it, is when it's in gear, also the car feels down on power. Any ideas on what that could be?

Did you ever resolve this? I have the exact same idle issue, there are so many variations but I've got the exact same climbing then dropping back and then climbing back up.