Sym ATTILA RS-21 EFi 150 Service Manual page 52

Diagnosis Of Idle Speed Misfire
Idle speed misfire
1. Connect the Data Scan
and check trouble content
2. Troubleshooting
according to the
troubleshooting
procedure.
Is fuel enough?
Are the battery wires
loose?
Is the vacuum hose
leaking?
This chapter Contents
4. FUEL INJECTION SYSTEM
If the idle speed misfire
problem still can not be solved
after check above related EFI
components item by item,
then check if the other
traditional components on the
engine is in abnormal.
Does the throttle valve
cable stuck so could
not be set-up?
Connect the Data Scan
and enter into CO
adjustment at idle
menu. Positive value is
for enrichment, and
negative value is for
lean.
Is the CO value in idle
speed out of set up
range? (0.5%~3.0%)
Does the carbon
deposited onto the throttle
valve body?
Does the by-pass valve
operate or out of order?
Replace with
new one for
confirmation
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