Problem fixed
. Completely new design for pressure differential sensor. (jpegs attached). No need to reset light on dash at Garage/Dealer. Took the fuel cap off for 20 seconds, put it back on and took it for a drive. Then took it off again, put it back on and eventually when you start the yellow engine light isn't lit.
Thanks for everyones input. Hopefully this can help people with similar problems. Obviously a design problem so probably worth replacing the old design sensor if you have any problems with FAP. If you have the old design pressure differential sensor and +5v is going into pin 3 -0v on pin 2 and you have anything other than 0.5v on pin 1 when ignition is on but engine not running then water has probably got inside and broke it. Paul
