I was getting off the highway this morning after my normal 20 minute commute to work. I released the gas, put on the brakes and felt the car shudder as I decelerated. (I've been wondering if it's normal for the car to shudder when decelerating quickly from high speeds, but that's a question for another day.) I'm sitting at the stop light for about 15-20 seconds when I see my RPMs drop from about 1,000 rpm's a minute to just below the 2nd hash mark on the tachometer. I think that should put it about 750 RPM's a minute. Is this low for this model, or is there something I should be looking into?

 

Just bought the car about a month ago, recently found out that it was previously owned by a Subaru mechanic out of Buffalo, NY, timing belt was changed, but I don't know much more than that. I'm waiting to get a hold of the previous owner to see if I can get any maintenance records on the car. As of right now the only thing I know for sure is that the oil was changed about 200 miles ago and the transmission fluid looks good.

Your idle is normal. The shuddering is probably your brakes and or rotors.  I would have somebody inspect your front brakes.

Makes sense, all the dealer did was slap new brakes onto old rotors. Good to know the idle rpm's are normal though.

750 is normal . 1000 is too high. Your shudder could be because the idle control valve is sticking.