Nissan Frontier D22. Manual - part 375

ENGINE CONTROL SYSTEM

EC-603

[VG33E]

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SYSTEM DESCRIPTION

If the engine speed is above 2,500 rpm under no load (for example, the shift position is neutral and engine
speed is over 2,500 rpm) fuel will be cut off after some time. The exact time when the fuel is cut off varies
based on engine speed.
Fuel cut will be operated until the engine speed reaches 2,000 rpm, then fuel cut will be cancelled.

NOTE:
This function is different from deceleration control listed under 

EC-599, "Multiport Fuel Injection (MFI) System"

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EC-604

[VG33E]

BASIC SERVICE PROCEDURE

BASIC SERVICE PROCEDURE

PFP:00018

Idle Speed/Ignition Timing/Idle Mixture Ratio Adjustment

UBS00DES

PREPARATION

1.

Make sure that the following parts are in good order.

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Battery

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Ignition system

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Engine oil and coolant levels 

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Fuses

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ECM harness connector

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Vacuum hoses

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Air intake system
(Oil filler cap, oil level gauge, etc.)

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Fuel pressure

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Engine compression

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Throttle valve

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Evaporative emission system

2.

On air conditioner equipped models, checks should be carried out while the air conditioner is OFF.

3.

On automatic transmission equipped models, when checking idle rpm, ignition timing and mixture ratio,
checks should be carried out while shift lever is in N position.

4.

When measuring CO percentage, insert probe more than 40 cm (15.7 in) into tail pipe.

5.

Turn off headlamps, heater blower, rear defogger.

6.

Keep front wheels pointed straight ahead.

7.

Make the check after the cooling fan has stopped.

BASIC SERVICE PROCEDURE

EC-605

[VG33E]

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EC

OVERALL INSPECTION SEQUENCE

NOTE:
If a vehicle contains a part which is operating outside of design specifications with no MIL illumina-
tion, the part shall not be replaced prior to emission testing unless it is determined that the part has
been tampered with or abused in such a way that the diagnostic system cannot reasonably be
expected to detect the resulting malfunction.

SEF554YA

EC-606

[VG33E]

BASIC SERVICE PROCEDURE

INSPECTION PROCEDURE

1. 

INSPECTION START

1.

Check service records for any recent repairs that may indicate a related malfunction, or a current need for
scheduled maintenance.

2.

Open engine hood and check the following:

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Harness connectors for improper connections

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Wiring harness for improper connections, pinches and cut

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Vacuum hoses for splits, kinks and improper connections

–

Hoses and ducts for leaks

–

Air cleaner clogging

–

Gasket

3.

Confirm that electrical or mechanical loads are not applied.

–

Headlamp switch is OFF.

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Air conditioner switch is OFF.

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Rear window defogger switch is OFF.

–

Steering wheel is in the straight-ahead position, etc.

4.

Visually check the following:

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Air cleaner clogging

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Hoses and ducts for leaks

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Electrical connectors

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Gasket

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Throttle valve and throttle position sensor operation

5.

Start engine and warm it up until engine coolant temperature indicator points to the middle of gauge.
Ensure engine stays below 1,000 rpm.

6.

 Open engine hood and run engine at about 2,000 rpm for about
2 minutes under no load.

7.

Make sure that no DTC is displayed with CONSULT-II or GST.

OK or NG

OK

>> GO TO 2.

NG

>> 1. Repair or replace components as necessary.

2. GO TO 2.

SEF983U

SEF976U

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