I'm sure this has been covered before but I couldnt for the life of me find anything with search function.
Have been experiencing a violent shudder when she reaches peak boost.
Watching the boost guage the needle will flutter where it normaly held firm.
Thought at first it may have been sparkplugs as they were due to be changed. Did so and no result.
Searched for vacume leaks and cant find anything visually, also used the brake kleen trick but had no luck there.
Checked the intake/bov/intercooler for excessive oil residue but everything seems fine.
No CEL and not sure where to look now. Any ideas?
Car has been well maintained and always run on Force 10.
Only thing I've done differently in the last 18 months is change from city driving to a 40km daily commute.