Corsa-B.uk - Vauxhall, Opel and Holden Corsa B Owners Club

The idle speed on my B seems a little high. (Around the 1500 RPM) and I know that they check idle speed on the MOT. Any ideas on how I can reduce this idle speed as cheaply as poss?! lol

If you start the engine cold it will Idle at around 1500 once the engine has warmed up it will idle at 1000 or just below.
Check that the idle changes when the car warms up.

does the car sometimes rev itself or when you depress the clutch or do the opposite and the revs drop so low that the engine stalls. These problems are caused by the idle control motor, you can take these out and clean them carb cleaner that ussualy fixes the problem.

In my car, when cold it idles at 2000 (!!) then drops to 1500. not sure about the revs fluctuating but I'm pretty sure they don't.

Different engines Idle at different speeds but they are alway around 1000 which engine do you have?

I don't think a high idle will fail an MOT but i'm not sure.

I would give the idle control motor a clean anyway

has the car always done this?

hello. it will fail mot because it is idling fats so spurting out more emissions on idle. i had the same problem and it may well be the idle motor which sits next to the throttle body