Symptoms:
the idle has not been good for a few years, but we have moved to a new league now.
My xf runs on Lpg and petrol, the problem appears on both, so the rules our a fueling issue I think
Over say 2000 rpm it’s as smooth as a baby’s bottom
I can not find any leaking tubes
I’ve changed the maf as it was a easy try
The fuel trims are all over the place at low rpm implying a vacuum leak, but I can find it. Sprayed carb cleaner around all joints and inspected all the pipework

A few questions please.
How do you remove the pvc pipes from the manifold, they don’t want to come out
How do I test if the brake servo is leaking and again, if they are pvc pipe how to remove them
Is there ICV or a EGV on these petrol engines, the manual is not clear

many thanks geoff