Hi Dave

I have never been rude to you , you do the job correctly and show professionalism.

I think you have identified the reason this car has a running problem.

Barometric pressure - is the clue.

68 millibar the PCM thinks the car is at 25,000 feet above sea level.

Barometric pressure (BARO) is inferred by the PCM software at part throttle and WOT there is no actual BARO sensor on MAF-equipped vehicles.

At high air flows, a faulty MAF sensor will under-estimate air flow coming into the engine, hence the PCM infers that the vehicle is operating at a higher altitude. The BARO reading is stored in Keep Alive Memory (KAM). What are Long Term Fuel Trims and short term trims like.

I would fit a new MAF and leave the PCM unplugged for 30min's , should clear down the KAM. But I have had some PCM's that would only seem to clear when instructed by WDS / IDS.

switch ignition back on without starting and the barometric PID should be around 998Mb also there may be a frequency PID for Baro that should 158.9hz.

Also one to remember on Ford ECC IV and V disconnect the MAF sensor connector. This puts the vehicle into Failure Mode and Effects Management some people also call it LOS (limited operating stratiges) .

In FMEM mode, air flow is inferred by using rpm and throttle position instead of reading the MAF sensor. In addition, the BARO value is reset to a base/unlearned value. If the lean driveability symptoms go away, the MAF sensor is probably duff.

HTH

Darren