Puff of smoke at High Rev and Air flow meter- CA20!

[aifte2000]

My mechanic says that its common for a CA20 to blow puff of smoke if you press the accelerator really hard when the car is at park. As he explains- at park the AFM measures a small(fixed) amount of air passing through it and sends the signal to ECU. However, as you press and hold the acceleration  really hard, the ECU momentarily injects more fuel compared to air intake and then tries to adjust fuel injection based on signal from AFM. BUT as the AFM sends a constant signal at park (as the air flow is fixed at park) and still you insist the ECU to increase Rev, it sends extra fuel at intervals and adijusts it next moment. This is why some interval based puff of smoke can be observed when accelerator is press for long at high rev.  To support his theory he showed me some computer tests and the computer says the car runs well within the HC, CO2  limit at high rev and idle and noway running rich.

Do you agree with him? Any new explanation! Thnx

[emuisme]

or it could just be the rev limiter cutting spark -> unburnt fuel -> black smoke as it gets burnt at the cat converter?

I had a little trouble understanding the post (not that I can talk about posting technique.

you are talking about an auto I assume? (not that I think that would make any real difference)