We've owned the 2002 S60 for 2.5 years and it always did this issue. It was my wifes daily driver but now it is my daily driver. The 2017 V50 T5 she now drives does not do this.

On the S60 it seems like the gas pedal is very, very ultra sensitive. When starting from a dead stop, you press it in and very quickly it will accelerate like a rocket and it is hard to smoothly take off. It is as if the turbo is engaging at a very low speed. Heck it almost jerks your head back but I have no problem with the V50 turbo.

The S60 has a K&N type air filter (dry washable filter). I've theorized that the air filter box being open, plus the filter type are at the heart of the issue.

No CEL, gas mileage is fine, runs well, etc. There are times when I am backing up the drive it hits that ultra acceleration and could be doing it when I am maneuvering between our other cars. Not a good thing.

Ideas appreciated.