This is why I always use a reliable mapper.
 

My car, a 98 UK car I've had since new in September 1998, had stood, mostly outside, for around six years.
It has a fully forged 2.5 after I managed to destroy the previous engine by heat soaking it and giving it too much right foot too soon. It wasn't helped by having had the heads skimmed after it had leaking head gaskets, and the local guy who did that didn't know about thicker gaskets to keep the compression ratio the same 🙄
So....18 months ago I decided to chuck some money at it and had the bodywork sorted properly, and a respray into Ferrari Rosso Corsa...it had been Subaru red bit it was dull and a bit faded.
Then it went to the engine builder for refurbishment, and waited there for a mapping day run by Bob Rawle of BR Developments.
I had the original LINK ecu from 2003 replaced with a G4X, and the car made 460. This was beginning of March.
Car was again garaged at home while we were in France.
Back on the road, insured for my eldest, he took it to show a fellow enthusiast, and reported it had lost fuel pressure, overboosted, then experienced rev cut and a loud pop in the exhaust.

I contacted Bob, who talked me through how to download the log of the run, and asked loads of questions.
I emailed him the downloaded logs.
He then compared them with the log of my mapping session, and rang me to ask me to check all three pipes from the boost solenoid were firmly in place and not perished or split.

Sure enough, the one to the turbo Waste gate had become detached at the turbo end...very difficult to see and get at.
I'd certainly not have found it without Bob's help.

iv been using bob for over 20 years now and he has always been super helpful