Join Date: Aug 2011
Location: Albuquerque, NM
Ferrari Life Posts: 11,856
Gus- 458 valves are fail open, so if a switch was not installed as Mark suggested or the vacuum hoses not disconnected from the pneumatic valves, the causes could be lack of vacuum due to a leak, a loose or removed vacuum hose(s), or a faulty bypass solenoid, of which there is only one on the 458.
On the 458 getting the valves to stay open continuously is as simple as pulling the hoses from the pneumatic valves and plugging the vacuum hoses to prevent ingestion of groad.
Whatever it is, should only take a few minutes to figure out what the problem is by a good technician. The Bypass Solenoid is number 20 in this parts catalog page from Ricambi's online catalog. In the second parts catalog drawing, you can see the pneumatic valves on the muffler cans, numbers 5 and 6.
Present: 575M 135171
Past: Dino 246 GT 02984, 365 GTB/4 14009, 308 GTS 25125
Every day I look around, and if nobody is shooting at me, it is a pretty good day.