Being my first Fiat out of the 110 cars I've owned, I am still learning my way around my Stilo Abarth (03 plate sillyspeed).

I have a flappy sound on low rpm acceleration (eg when pulling off from stand still) - a classic manifold gasket leak sound I think. However I pulled the heat shielding off the exhaust manifold and cat but can see nothing because of whatever it is directly above (not sure yet if its the head or a separate thermostat housing etc). Anyone got any thoughts on how I can get to the manifold gasket to see if its leaking? Or is there a chance its the inlet manifold/gasket (though I'd expect running issues if that was the case, but one never knows)? Seems to be a common'ish problem so thought I'd check for any tips/pointers etc.

Plugged my 327 in yesterday and got:
P0707 - clutch switch - invalid signal
P1555 - - signal low
P0235 - Boost pressure sensor -

The clutch switch is above the brake pedal correct? But what about the boost pressure sensor?

Thanks for all thoughts and help!

Apart from these bits and a missing metal contact plate for my + gear paddle (annoying to have to replace the whole paddle just for the sake of a tiny piece of metal), everything else is going fine so far

P1555 occurs if you press the brake and accelerator pedal at the same time. The ECU doesn't expect that to happen so gives the fault code.

P0235 is a Turbo Charger boost valve code. As the Abarth engine doesn't have a turbo, it would suggest that you code reader isn't reading correctly.
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