A Question about revs...

[balders118]

Recently I have noticed a behaviour my car has that I can't explain. I'm not sure if is supposed to do it, or if it's breaking.

If I just roll away, once the speed gets up to 5mph the idle picks up from around 900rpm, to 1200 ish. Like wise, if I slow from speed and put the car into nuetral while still moving, the revs will stay at about 1500 until the car has been stopped for a moment or two.

So, is there a reason for this? Or is my car doomed? I can't say i've noticed it any other car in all my years of driving.

[mnkiboy]

I think most cars do that. I presume to build up the required vacuum for full braking power, if required.