Yingang YG125-30B, Manual

Page: 149 / 151

YG125-30B Maintenance Manual Engine management system
155
S
ta
rt
D
if
fi
cu
lt
Check wether the fuel pump pressure is about 250kPa at idle.
Yes Next
No Check the pump.
Pull out the spark plug, check whether the sparkover is normal.
Yes Next
No Check the ignition system
Remove the connector of the engine temperature sensor, and
check whether the enigne start well.
Yes
Check the engine
temperature sensor
No Next
With a little bigger throttle, check wheterh the engine starts
well.
Yes
Clean the throttle body and
bypass channel.
No Next
Pull out the injector, and crank the engine. Check whether the
injection is normal.
Yes Next
No
Clean or change the
injector.
Pull out the sprk plug, check whether it is wet or not
Yes
dry the plug and
combustion chamber.
No Next
Check whether the cylinder pressure is normal or not
Yes Engine is good
No Check the engine
U
n
s
tab
le
id
le
Check whether the air filter is blocked and whether the intake
pipe leaks.
Yes Intake system maintenance
No Next
Whether there is carbon deposit at the throttle body and bypass
channel.
Yes Clean the TB
No Next
Check whether the IACV works well
Yes Next
No Check the IACV
Check whethe the fuel pressure is about 250kPa.
Yes Next
No Check the pump
Check whether the injeoctor is blocked.
Yes
Clean or change the
injector
No Next
Make sue using the right type sprk plug
Yes Next
No Change the spark plug
Check whether the cylinder pressure is normal
Yes Next
No Check the engine
Remove the engine temperature sensor, and check whether
the engine works well
Yes Change the senor
No Next
Remove the TPS, check whether the engine works well
Yes Change the sensor
No Help
H
igh
id
le
Check whether the throttle cable is stuck
Yes Adjust the cable
No Next
Check whether the idle pintle has been adjusted
Yes Change the TB
No Next
Check wehther ther is any leakage of the intake pipe.
Yes Maintenance
No Next
Check whether the IACV works well
Yes Next
No Change IACV
Remove the engine temperature sensor and check whether the Yes Help