I've got a MAP sesnor error code on my FSI and have just been checking that the sensor is getting 5v power to it. there are 3 pins. Elsawin shows pin 3 should be 5v and pins 4 and 1 should be 'sender earth'. when i checked the voltage getting to the pins with ignition on i see 5.1v at pin 3 as expected, 0.1v at pin 1 as expected, and 5.6v at pin 4. Is this correct or could this be the problem? i'm just trying to rule out the wiring before stripping it down to change the sensor. many thanks