Great Wall GW491QE, Руководство по обслуживанию

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EF.2-15
Delphi฀engine฀management฀systm Determination฀on฀the
principal฀/utility฀/failure฀of฀key฀system฀parts
12.฀A i r฀inlet฀system
Function฀ &principal
T he฀function฀of฀air฀inlet฀control฀system฀is฀to฀supply฀an฀appropriate฀amount฀of฀air฀based฀on฀the฀requirement฀for฀engine฀dynamical
output.฀T he฀air฀inlet฀control฀is฀divided฀into฀active฀control฀and฀system฀auto.฀control:฀the฀former฀means฀to฀control฀the฀enginedynamical
output฀by฀actively฀adjusting฀the฀opening฀degree฀of฀throttle฀valve฀in฀accordance฀with฀various฀demands฀of฀driver฀on฀engine฀dynamic
force;฀฀And฀the฀latter฀means฀to฀stabilize฀the฀work฀of฀engine฀฀(eg closed-loop฀control฀for฀engine฀idle-speed)฀by฀systemauto.฀adjusting
the฀air฀inlet฀amount฀in฀accordance฀with฀information฀feedbacked฀from฀the฀closed-loop฀control฀monitor.
฀฀฀฀฀(c)Characteristics฀of฀product Output฀signal
฀฀฀฀฀Frequency฀฀฀฀฀฀฀Output฀signal
฀฀฀฀5kHz฀฀฀฀฀฀฀฀฀฀฀฀฀฀฀(17~37)mV/g
฀฀฀฀8kHz฀฀฀฀฀฀฀+15
5kHz
฀฀฀13kHz฀฀฀฀฀+30 ฀when฀at฀5kHz
฀฀฀18kHz฀฀฀฀Two฀times฀of฀that฀when฀at฀13kHz
฀฀฀฀It’s฀always฀>17mV/g฀under฀no฀circumstance.
Range฀of฀frequency฀response (3~18)kHz
Capacitor 1480~2220pf when฀at25 1000Hz
Resistance >1M ฀ when฀at฀25
Working฀temperature ~
(b)Failure฀determination
Importantnote: Either฀of฀following฀determinations฀may฀beconcluded
based฀on฀that฀the฀whole฀vehicle,฀its฀wire-harness,฀and฀other฀system
parts฀&components฀are฀normal฀in฀function.Failure฀diagnosed฀by฀the
system฀may฀be฀read฀out฀from฀a฀Diagnosis฀Instrument
The฀signal฀in฀wire-harness฀has฀not฀adopted฀shielded฀฀wire,฀or฀its
shielded฀layer฀has฀not฀been฀well฀grounded.
air inlet control system
throttle valve unit
valve unit
throttle sensor
idle-speed control valve
13.฀Throttle฀valve฀assembly
(a)Function฀&principal:
-The฀function฀of฀throttle฀valve฀is฀to฀control฀the฀air฀inlet฀amount฀while
engine฀is฀working,฀and฀may฀be฀regarded฀as฀the฀most฀fundamental฀channel฀for
a฀“talk”฀across฀the฀electrical-injection฀system฀and฀the฀driver;
-Throttle฀ valve฀ is฀ composed฀ of฀ valve฀ unit,฀ valve,฀ acceleratorrod
mechanism,฀throttle฀position฀sensor,฀idle-speed฀control฀valve,฀etc.
-฀Some฀throttle฀valves฀have฀one฀coolant฀pipeline฀installed฀on฀the฀bottom,
which฀may฀be฀used฀to฀prevent฀icing฀within฀valve฀plate฀area฀when฀engine฀is
working฀at฀a฀cold฀temperature฀as฀hot฀coolant฀heat฀by฀engine฀will฀pass
through฀this฀pipeline;
-Installation Throttle฀valve฀is฀installed฀in฀front฀of฀the฀inlet฀manifold.
(b)Failure฀determination:
Important฀note
E ither฀of฀following฀determinations฀may฀be฀concluded
based฀on฀that฀the฀whole฀vehicle,฀its฀wire-harness,฀and฀other฀system฀parts
& component฀are฀normal฀in฀function.฀A฀regular฀wash฀is฀needed฀as฀the฀valve
and฀its฀idle-speed฀hole฀might฀be฀blocked฀by฀oil฀sludge.
(c)C har acter istics฀of฀pr oduct
-Diameter฀of฀throat฀opening ฀ 38฀mm
-Diameter฀of฀idle-speed฀valve฀hole ฀ 10฀mm
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