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MAF and MAP Standard Readings 2013 150 Prado 1 KDFTV Black Smoke

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  • MAF and MAP Standard Readings 2013 150 Prado 1 KDFTV Black Smoke

    Hi all

    I have recently noticed my exhaust becoming excessively black, to the point that even low load on flat road not much more than idle it leaves a haze behind.

    When giving it a boot load it bellows with black smoke, and even when steadily increasing the throttle when stationary and giving it a gently rev it blows quite black.

    The vehicle is otherwise well maintained, has ~160km on the clock, injectors are ~20k and 14 months old, air filter is fresh, manifold should be clean as it was cleaned completely after I added a catch can.

    The engine also idles fine, and seems to run fine apart from a very intermittent low boost condition that goes away on restart which I believe is unrelated.

    I performed some diagnostics today to try and assess the health of the MAF sensor, idea was to determine if the MAF readings increased in a linear fashion at 250rpm increments - and they do.

    What I did discover though were a few peculiarities in the figures which I was hoping could start some discussion.

    From a cold start the MAF reading at idle (802rpm cold engine) was 9.1 g/sec up to around 55 degrees coolant temp. I also noted that the MAP was 78kpa (ambient was 101kpa).

    Then whilst the engine warmed up I noticed an audible change, hard to describe but like it was lower pitched. At the same time the MAF reading at idle (now 700rpm) went to ~18 g/sec and steady.

    The at idle MAF did not change from there remaining between 16 and 18 g/sec.

    I thought this was a bit high, and I am struggling to find a good reference for expected normal MAF readings.

    What I did also notice was that the MAP (Manifold Pressure) was still low at ~80 kpa. So I shut the engine down to assess the MAP with no pressure, and it was still around 80 kpa. The Barometric Pressure readout was steady at 100 kpa and I am almost at sea level and the current actual atmospheric pressure is 101 kpa.

    By my logic I would assume with the engine off the MAP should be close to or equal to the Barometric Pressure. Am I correct in this thinking?

    For reference my MAF readings were, and when charted these are near linear:
    RPM MAF g/sec
    913 24
    1250 36
    1480 43
    1750 52
    2000 59
    2250 66
    2500 77

    So questions:
    • Could this cause the engine to run rich?
    • Does anyone have a reference MAF reading chart for the 1 KD FTV?
    • What is a normal MAF reading at idle