Impco HHI, Руководство по обслуживанию

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LACK OF POWER, SLUGGISHNESS, OR SPONGINESS
Checks Action
DEFINITION: The engine delivers less than expected power. There is little or no increase in speed
when partially applying the accelerator pedal.
Preliminary Checks

Refer to the Gas Fuel system OBD System Check.

Compare the customer’s vehicle with a similar unit to verify customer has
an actual problem.
Do not compare the power output of the vehicle oper-
ating on gas to a vehicle operating on LPG as the fuels do have different
drive feel characteristics.

Remove the air filter and check for dirt or restriction.

Check the vehicle transmission.

Refer to the OEM transmission diagnostics.
Fuel System Checks

Check the in-line fuel filter for restrictions , contaminated fuel, or improper
fuel pressure. Refer to Gas Fuel System Diagnosis .

Check for fuel pump electrical circuit.

Verify proper fuel pump pressure.

Verify proper fuel rail pressure.
Sensor Checks

Check the Heated Exhaust Gas Oxygen Sensor (HEGO) for contamina-
tion and performance.

Check for proper operation of the MAP sensor.

Check for proper operation of the TPS and FPP sensors.
Exhaust System Checks
Check the exhaust system for a possible restriction:

Inspect the exhaust system for damaged or collapsed pipes.

Inspect the muffler for signs of heat distress or for possible internal failure.

Check for possible plugged catalytic converter.
Engine Mechanical
Check
Check the engine for the following:

Engine compression.

Valve timing.

Improper or worn camshaft.

Refer to Engine Mechanical in the Service Manual.

Check for the proper ignition output voltage with the spark tester J 26792
or the equivalent.

Check electrical connections of fuel injectors.
Additional Check

Check the ECM grounds for being clean, tight, and in their proper loca-
tions.

Check the generator output voltage.
If all procedures have been completed and no malfunction has been found,
review and inspect the following items:

Visually and physically, inspect all electrical connections within the sus-
pected circuit and/or systems.

Check DST data.