Motive Power Industry BLUR 150, Service Manual

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(10) Start-up normal but idle speed too high
General trouble location: 1. Air throttle and idle air bypass; 2. Vacuum tube; 3, ISC ; 4. Engine
temperature sensor; 5. Ignition timing.
Procedure for general diagnoses:
No. Operating Procedure
Detection
Results
Subsequent Steps
Yes Adjustment
1 Check the throttle cable for jammed or too tight.
No Next step
Yes
Repair the air intake
system.
2
Check the air intake system and the connected vacuum tube
for any leakage.
No Next step
Yes Clean relevant parts.
3
Remove the ISC and check the air throttle, the ISCand the idle
air bypass for any carbon deposition.
No Next step
Yes
Correct circuits or
replace any sensor.
4
Press the engine temperature sensor connector and start the
engine; check if the engine’s the idle speed is too high.
No Next step
Yes Next step
5
Check if mechanical ignition timing of the engine is
conformable to specifications.
No
Correct ignition
timing.
Yes Diagnosis assist
6
Connect an EMS adapter and press the power switch to check
voltages at Pins
1#, 19#, and 29#
; check grounding at Pins
8#
﹐
35
#
and
36#.
No
Repair the relevant
circuits.
35