Specifications

77
Data Parameters Engine Parameters
are a lean correction, or reduced injector time. The ECU attempts to compensate for tolerances
in the mixture by means of LTFT adjustments. All corrections are made in three ranges: closed
throttle position, lower partial load, and upper partial load. The ECU multiplies the actual mass of
the air inducted into the engine by the correction factor to determine the injection time. For
example, if the actual air mass is 150 kg/h and the Scanner reading is 1.10, a computed air mass
value of 165 kg/h (150 x 1.1 = 165) is used for injection time.
SELF-ADAPT. CTP (IDLE) LEFT
SELF-ADAPT. CTP (IDLE) RIGHT
Range: _____________________________________________________ –1.0 to 1.0 ms
Used on ME10 and ME20 systems. These parameters display the closed throttle position (idle)
fuel correction for the indicated cylinder bank the ECU is commanding to maintain a 14.7:1, or
1.0 Lambda, air-fuel ratio. The display is the adjustment made in addition to basic injector on
time. There are three ranges in which self-adaptation, or long-term fuel trim (LTFT) is performed:
closed throttle; lower part throttle, and upper part throttle. If short-term fuel trim (STFT) or O2S
Lambda control constantly drifts out of mid-control range, the ME control module shifts the
Lambda map to recreate a control factor of about 0%. Idle speed-learn, or SELF-ADAPT, is in
millisecond output. The readout is added to or subtracted from the air mass inducted by the
engine for determining injector time. For example, base injector time is 3.0 ms and SELF-ADAPT
CTP (IDLE) LEFT reads 0.3 ms. This means that the ECU is using a computed value of 3.3 ms
for determining injection time on the left bank.
SELF-ADAPT. DELAY TIME LEFT
SELF-ADAPT. DELAY TIME RIGHT
Range: _____________________________________________________ –1.0 to 1.0 ms
Used on ME10 and ME20 systems. These parameters display the left and right cylinder bank
adaptation for injector delay time. Delay time is supplementary injection duration based on
battery voltage. Injector duration varies according to battery voltage and there can be substantial
time lag before the injector opens completely, especially during cold starts or with a partially
discharged battery. The display represents the supplementary injector on time in (ms) that is
being added to the base duration to compensate for this effect on the left cylinder bank.
SELF-ADAPT. FACTOR LOWER PART. LOAD
SELF-ADAPTATION LOWER PART. LOAD
SELF-ADAPTATION PARTIAL LOAD
Range: ________________________________________________________0.85 to 1.15
Used on LH and HFM systems. This parameter displays the lower partial load self-adaptation
factor, which is one of three factors the ECU uses to make long-term fuel trim (LTFT) corrections
to maintain a 14.7:1, or 1.0 Lambda, air-fuel ratio. A 1.0 reading represents the base point.
Readings greater than 1.0 indicate a rich correction, or increased injector time, and readings
below 1.0 indicate a lean correction, or reduced injector time. The HFM-SFI control module
attempts to compensate for tolerances in the mixture by means of LTFT adjustments. All
corrections are made in three ranges: closed throttle position, lower partial load and upper partial
load. The ECU multiplies the actual mass of the air inducted into the engine by the displayed
correction factor to determine the injection time. For example, if the actual air mass is 150 kg/h
and the Scanner reading is 1.10, a computed value of 165 kg/h (150 x 1.1 = 165) is being used.
SELF-ADAPT.PART. LOAD FACTOR RIGHT
SELF-ADAPT.PART. LOAD FACTOR LEFT
Range: __________________________________________________________ variable
Used on ME10 (0.77–1.28 range) and ME20 (0.68–1.32 range) systems. These parameters
display the lower partial load self-adaptation factor for the indicated cylinder bank. Lower partial
load self-adaptation factor is one of three factors the ECU uses to make long-term fuel trim
(LTFT) corrections to maintain a 14.7:1, or 1.0 Lambda, air-fuel ratio. A 1.0 reading represents