I checked all the DTCs on my TDV8 at the weekend and noticed a new code that I had not seen before, P023D - MAP - Turbo charger boost sensor A correlation signal amplitude > than max.

Driving home yesterday, I could see fairly thick black smoke under load/acceleration but no engine management light or limp home issues yet.

This and the error code suggests incomplete combustion to me, so it thinks it is getting more air than it actually is and so ends up with too must fuel. That lines up with what the error code seems to say.

On research of this forum and a few other places, seems it could be a number of things, all air inlet related, including sticking turbo actuator, split in the inlet system (seems like intercooler pipes are an issue), possible MAP sensors need cleaning/replacing), possible leaking inlet manifold (looks like a big job to replace).

I've stopped driving it for now (Time for the Alfa Spider to re-emerge from hibernation) and will investigate at the weekend starting with the easy and visible things and going through to the harder things.

Wish I had a smoke gun and am considering making or buying one out of interest sake to see if it can show the leaks, especially if I get as far as suspecting the inlet manifold.

I assume the A means its UK drivers side?

Intercooler top pipes often fail, so would be my first check. Dead easy to replace too, which is nice. 2012 SDV6 - it's missing a couple of cylinders
2008 TDV8 - it was a labour of love and is much missed

Had this issue on an old autobiography sport TDV8.

Pipe connection at the intercooler was split on the underside. Ran a finger round and was shocked at how bad the burst was. I think i wasn't more than 50 quid for genuine hoses at the time, replaced both iirc. RRS SVR Estoril Blue, Huracan Performante Spyder Rosso Mars, Tesla Model X Black

Looks like hoses will be the first place to look.

Thanks for the guidance. I will report back!

Top passenger side intercooler hose with a 6cm split.

Weird that the error code suggests the drivers side.

Cleaned the MAP sensors and checked the actuators are moving freely. Now just waiting for a hose to arrive on Tuesday.

New hose installed, car runs much smoother and responsive now (and less soot out the back as you'd expect), and no error codes appearing.

Thanks for the direction and ideas given.