Hi John

Thanks for the thought. If the pressure sensor is infact the actual barometric sensor, then wouldn’t it update “live” in live data & not like the “snapshot” reading taken from the MAF setup? I unplugged the sensor & there was no shift from 68mb & no fault code logged. Also I did get a digital signal capture from the sensor that looked ok.

I was thinking about what Darren said, regarding Barometric pressure being inferred. I am struggling to see how the PCM can determine this value from the MAF sensor. From my understanding, the MAF calculates airflow by looking at the amount of current required to maintain a temperature of 200ºC in the "Hot Wire" (crudely explained). If a Barometric pressure value is to be calculated at start-up & wide throttle openings, I would be interested to know how, as this is not a pressure transducer.

I have just been looking at Ford TIS & reading about the VI system (variable inlet system). I do recall seeing the letters "vi" on the inlet manifold. TIS also mentions secondary air injection, which I maybe haven’t looked at hard enough

I am looking forward to getting my hands on this car again, so that these questions can be answered

Cheers again.

Dave (Hill)