Hisun HS200UTV - Starting Failure;Hard Starting

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ENGINE MANAGEMENT
SYSTEM
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 Install the retaining clip after connecting the fuel line
 Tighten the injector mounting to the desired torque as mentioned in the manufacturer
manual
 Tighten the fuel line
 Re-install the injector electrical connector
 Check for fuel leaks with the key “on” and the engine “off”
 Start engine and verify proper operation.
5．Plugging
Fuel deposits cause plugging resulting in flow shifts over the life of the injector. Fuel varnish or
gumming, a type of injector deposit, is created when certain types of fuel are heated by high
injector tip temperatures at soak (no fuel flow). Deposit build up in the director holes causes
the flow shifts
 Plugging can cause flow restrictions, frictional changes and the collection of other particles
attracted by the tacky surface. The flow restrictions can degrade emissions and drivability.
 Other fuel and environmental conditions may cause crystal or corrosion growth in the
injector and cause a flow shift.
 Oxidation stability of the gasoline affects the potential for deposit formation and must be
controlled by the fuel supplier.
 Increased levels of detergent additives reduce the rate of injector plugging.
 Incase of plugging of injector follow the injector cleaning procedure mentioned in the section
below
6．Cleaning Procedure
 Electrically disable the fuel pump by removing the fuel pump connection.
 Relieve the fuel pressure in the system and disconnect the fuel connection at the injector.
Plug the fuel feed line.
 Injector cleaner with the specific ratio of the cleaner and gasoline to be mixed in the Injector
cleaning tank.
 Connect the injector-cleaning tank to injector in the vehicle.
 Pressurize the injector-cleaning tank to system pressure.
 Start and idle the engine for 15- 20 minutes.
 Disconnect the injector-cleaning tank from the system and install the fuel pump connections.
Connect the fuel feed line to injector.
 Start and idle the vehicle for an additional 2 minutes to ensure the residual injector cleaner
is flushed from system.
Throttle Body Assembly(with stepper motor)
1．Description and Working Principle
The Throttle Body Assembly is an interactive system comprised of the following
subsystems: the main casting body, bearing system, shaft and valve system, return spring
system, cable interface system, throttle position sensing system, and the bypass air control
system. The subsystems interact and support each other to provide all the functional
ENGINE MANAGEMENT SYSTEM
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requirements, which are mentioned below -
 Control intake air flow
 Control idle air flow
 Sense throttle position - Provide position feedback to Engine Controller
 Provide reactionary force to the throttle
2．
Handling – DOs and DONTs
THROTTLE BODY ASSEMBLY HANDLING
ACTION REASON
DO:
Use care during assembly of harness to throttle
body.
Avoid terminal damage.
DO: Avoid any liquid contamination in the throttle
body area.
Ensure proper operation.
DO: Unload and install units one at a time from
packing trays.
Damage may be done to critical components.
DO: Return any dropped, damaged, or suspect
material with a tag that describes the problem.
(Only warranty cases)
Ensure fast and correct diagnosis of root
DO: Remove and discard protective caps just before
assembling mating components.
Protects system from contamination, which
can prevent proper operation.
DO: clean the by pass passage after removing
bottom cover
To ensure good idle stability
DO NOT: Use any dropped or impacted unit.
Internal damage may have occurred o
r
emissions settings may have been upset.
DO NOT: Store units without protective caps in place. Contamination may impair correct operation.
DO NOT: Ship or store near saltwater without
protection.
Corrosion buildup may impact prope
r
operation.
DO NOT: Exposed to environmental conditions
(Moisture) prior to complete vehicle
installation.
Corrosion buildup may impact prope
r
operation.
DO NOT: Apply any voltage other than system
voltage for testing.
Damage could occur.
DO NOT: Apply excessive band clamp loading Damage could occur.
DO NOT: Remove packing in a way that allows
contact between parts.
Minimum air leakage could be affected
and/or other damage could occur.
DO NOT: Release the throttle cam abruptly from any
position without the throttle linkage
attached.
Damage could occur.
DO NOT: Let the by pass holes be blocked by dirt or
foreign particles.
This could effect idle stability
DO NOT: Rake, stage, or handle parts in a manner
that allows contact between parts.
Damage will occur.