My 1998 Volvo V70R with only 53,000 miles (I’m the orignial owner) has picked up a problem. It started a year ago and seems to occur only when I do not let the car warm up for a few or several minutes: once I put the car into drive and start to move – no matter how slowly – a loud, high speed whirring sound begins. It will last for a minute or two and then stop. The speed of the whirring is constant and is not affected by how fast I drive or even if I come to a stop. It happens in both cold and hot temperatures. The whirring does not occur if I start the car and just let it idle and warm up. The loudness of the sound is such that it can be distracting to pedestrians 40 feet away. Changing the oil hasn’t helped. More recently, the noise sometimes reoccurs in the middle of a drive. It always occurs when I start the car after it’s been sitting for a few hours or more. Any ideas?
You drive this car about 2k miles per year? Having owned a couple of V70XC’s (an '98 and 2000) you’d best part company with the car soon. Your cost per mile to keep it is going to get outrageous. Who knows what this noise is, perhaps the electric cooling fan for the radiator/AC is going out with a bad bearing. Sell it, and sign up for ZIP car for the few miles and times you need a car.
The noise you hear might be from the secondary air pump.
This is an electric motor/fan that introduces compressed air into the exhaust system to light off the catalytic converter.