4000CS Quattro L5-2144cc 2.14L SOHC (JT) (1986)
Barometric Pressure Sensor: Description and Operation
Fig. 4 Altitude/Current Graph
The amount of fuel sent to the injectors is affected, in part, by the signals to the ECU from the altitude sensor, Fig. 3.
As altitude increases (decreasing air pressure) the mixture will be adjusted by a reduction of the differential pressure regulator current. Reducing
the current lowers the lower chamber pressure in the fuel distributor and leans the fuel mixture. The altitude sensor continuously adapts the
injected fuel quantity to the changing air pressure.