u/Life_Ad3346

I suspect I have a warped exhaust manifold, high pitch squeal when cold on the odd occasion (thought it was the fan belt) hissing/whooshing noise that builds with the engine revs, turbo boost pipes checked, intercooler checked and all fine, but no loss of power as far as I can tell, no exhaust stains on the engine block, any ideas on how I can crack down on the issue and confirm if it’s an exhaust manifold or something else I’ve looked over? I have until Friday to fix it otherwise I have to cancel my trip!!! Oh and the exhaust manifold already has upgraded studs and has been dewebbed which suggests to me this has been a problem in the past

2003 16p TD5 defender 110, 240k miles