Skoda Octavia 1997 Workshop Manual page 35

OCTAVIA 1997 1.9/74 kW (TDI) Engine, Fuel Injection and Glow Plug System
Analysis: Display group 013, display field 1 to 4
- idle smooth running control
The injection system has an idle smoothness regula-
tor. It is possible to detect differences in performance
between individual cylinders (part tolerances, injector
flow, compression etc.) and to compensate for these
by selectively metering the quantity injected in the
idling speed range.
Differences are detected in the idling speed range on
the basis of the signal supplied by the engine speed
sender which supplies four signals to the control unit
for each crankshaft revolution. If the signals have the
same rhythm, the cylinder have the same output. If a
cylinder has a lower output, the crankshaft will need
more time for the next half crankshaft rotation. As op-
posed to this a high output cylinder will accelerate the
crankshaft to such an extent that it will need less time.
Once the control unit has identified a deviation, the
relevant cylinder will immediately be supplied with a
greater or smaller injection rate until the engine again
runs „smoothly".
+... mg/s: The relevant cylinder has less output and is
therefore supplied with more fuel.
-... mg/s: The relevant cylinder has more output and
is therefore supplied with less fuel.
Display group 016 in idle
Read measured value block 16
xxx % xxxxxxxx
1 2
Generator capacity
Analysis: Display group 016, display field 2 - Auxiliary heating
X X X X X
1
1
Edition 12.03
S00.5139.52.20
< Readout on display
xx xx.x V
3 4 < Display field
Supply voltage of the en-
gine control unit
Heating element control
Auxiliary heating
Meaning, if display positions = 1
X X X Additional heating deactivated, because:
1 Coolant temperature greater than 70...75 °C or intake air temperature
greater than +5°C
1 Generator defective
1 Battery voltage below 9 V
Engine speed less than 800 rpm
Engine start within the last 10 seconds
Self-diagnosis IV
Specification Analysis
13,5...14.5 V
page 8
xx
page 8
1x00001
page 7
5...95 %
01-4
01
01-4
01-4
01-4
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