[mikefocke]

So lets start with it is a 24ish year old car at best.

Maintenance history?
Porsche specific diagnostic tools available (PIWIS, PST2, Durametric, ?)?
Last time the intake and throttle body were cleaned and how?
How old are the MAF and O2 sensors?
Looked at the condition of the plugs?
Ever used injector cleaner?
How old is the fuel? Octane high enough?
Are all the hoses good?
AOS age?

Just random thoughts...