Picked This up on the Aldous Voice blog and may be of use if you have variocam issues :dont know:
AV is by default a Ferrari 360 valuer/expert and I tend to use his 'market watch' as a baromoeter for 993 prices :grin: Albeit I have my own valuation tables :hand:
Ive book marked it for further referance as ive already diagnosed these as being faulty for members here and i didnt have any picts / insructions to show them .
I had a very similar issue, there is a similar solenoid that actuates the variable valve timing (as opposed to the variable valve lift) threw up a p0018 or 08 code (can't remember which)
Very quick fix from my local Indy (Nine Excellence). Hey can get a bit sticky I'm told.