i purchased a new to me automatic 07 s40 2.4i 90,000 miles. love the car but three months into owning it i started to get a weird metallic rattling noise. almost like an exhaust shield rattle, controlled by the throttle. shields all seem in place and strong. it happens from 25-60 mph when the car is called to down shift from 4th or 3rd to accelerate this noise becomes louder and. let off the throttle and the noise stops. Cannot recreate the noise while car is parked. must be ing drive and happens more when its cold. i also have a check engine with the code of p0026. research has pointed me to solenoid behind oil cap.

any insight to the noise, or if the code is related would be helpful.