[ersatzS2]

It probably has an altimeter as one of the sensors feeding into the ecu. The only turbo engine I have intimate familiarity with is the fabulous old Audi I-5 20v 2.2 turbo. It had an altimeter as one of almost 40 different ecu sensors. Sorry to contribute conjecture rather than fact specific to the 135 engine, but rest assured that high altitude performance has always been a forte of turbo engines, and was a big factor in Audi's period of Pike's Peak dominance.