Fuel fail 13 fault code 93 XJ12 6.0

[naki]

Fuel fail 13 fault code 93 XJ12 6.0.
Inlet manifold pressure warning.

I have had this fault come up today on a V12.
The engine was running, then cut out.
I have some some net searching but I can only find some info on the XJS version mentioning a manifold pressure sensor? But I can’t find any sensor on this on the 93.
I did find a vacuum hose off. I thought replacing it has fixed it. But the fault returned despite the hose being on position.
The engine starts dying. It’s possible there’s another hose damaged or off, or other vacuum leak. But I have not found any else a miss yet.
The blanking caps are in place under the inlets.
Has anyone experienced this on a 6.0?

I just had the Extra air valve off today, cleaned out and refitted. I wonder if that has triggered it somehow?
Another post I read, the XJS owner had the issue after replacing a Heater matrix.

[naki]

I think I will check this hose pictured (no.4 & 5). to see if that’s come loose. Since it’s attached to the air valve, it could conceivably have come loose since I moved the valve.

.

[naki]

For reference, those car has all new Ignition parts fitted (only the ignition amps are used, but everything else including the coils are new). So everything is good on the ignition side.

I am aware of the multitude of vacuum hoses. I had previously checked them/ all I could see. But it’s possible a part is problematic in a hidden place.

[naki]

A small update on this. It seems the fault code was a symptom, rather than a cause. So far as I can tell, I had a broken wire on the heated oxygen sensor relay plug, which caused an intermittent connection/ high resistance. Which was then cutting the fuel out/ causing the engine to stumble/ stall. This inadvertently triggered the fault code. I assume the manifold pressure was dropping as the engine was stalling.
Anyhow. It’s early days for this car. So let’s see what happens next.