A few days ago my car started making a squealing noise whenever I accelerate between 20-45 mph. As soon as I let off the gas, the noise stops. And when I am at a constant speed (normally 45mph for main roads and 70 on highway) it stops. Also on the highway it takes forever for it to speed up to 70mph... My service vehicle light came on soon before this problem happened and I just want an idea of what is wrong before I drop it off to a shop. Any thoughts would be appreciated!