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The 101F01 diagnostic trouble code (DTC) on the BMW 535i (also FC 28A0) means that the Throttle Valve is open too much, specifically when comparing the pressure inside the intake pipe to absolute pressure. This issue is usually caused by a short circuit in the interface rather than a problem with the throttle valve itself. There's a BMW technical service bulletin (TSB) related to this problem, labeled as S1 B11 09 19. Sometimes, this fault code may pop up after you've reset the battery for a different repair. To address this, BMW suggests unplugging the tank ventilation (purge valve) electrical connector, letting the engine idle for 15 minutes, then reconnecting the connector, clearing the fault code, and finally driving the 535i around for about 10 miles to make sure everything is back to normal.
A problem with the intake manifold pressure sensor is leading to the BMW 535i displaying code 1010f01.
Based on my own firsthand experience, I discovered that carbon buildup on the inlet valves was the root cause of this issue. Despite trying numerous replacements and tests, only following BMW's walnut shell blasting instructions on the inlet valves actually solved the problem. I can attest to this since I was the one who performed the work.
I understand your frustration, John. I've been dealing with a similar issue of replacing parts only to have that darn 101F01 code keep showing up. It's fantastic that you were able to identify the problem at last.