[xj-s] Stumbling and Cursing, part 4:

Re my earlier query, I forgot to mention that when the acceleration/power
stumbles (and I curse), the “check engine” display on the OBC comes on. The
reference code is “FF 13”, which my list says is “Pressure Sensor”.
However, I’m not even sure what the pressure sensor is, let alone whether
the code reference diagnoses a problem, a symptom, or an artifact. Does
this help with the diagnosis for anyone?

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