QX4 V6-3275cc 3.3L SOHC MFI (VG33E) (1998)
Engine Control Module: All Technical Service Bulletins
Engine - Hard Cold Start at High Altitude
Classification:
EC98-026a
Reference:
ITB98-047a
September 15, 1999
1997-99 QX4 HARD START AT HIGH ALTITUDE AND COLD CONDITIONS
This amended version of ITB98-047 updates information in the Applied Vehicles, Applied VINs, Applied Dates and Parts Information sections. Please
refer to this bulletin (ITB-047a) for complete information.
Note:
This bulletin supersedes ITB97-025.
APPLIED VEHICLE:
1997-99 QX4 (JR50)
APPLIED VIN:
Vehicles built before JNRAR05Y*XW047868
APPLIED DATE:
Vehicles built before September 4, 1998
SERVICE INFORMATION
If a 1997-99 QX4 is difficult to start at high elevation (over 5,000 ft.) and/or low ambient temperatures after a 4-6 hour cold soak, use this bulletin to
diagnose and repair the incident.
The cause may be insufficient air volume through the AAC valve while cranking. New parts (AAC valve assembly and ECM) are available for this
incident.
The vehicle may be towed in with a complaint of no start or driven in with a complaint, but no symptoms evident at the time. The incident may be
duplicated at the dealership if temperature and altitude match the above referenced conditions.
Hard starting may also occur if base idle speed or ignition timing is out of specification.
SERVICE PROCEDURE
Check for Other Hard-Start Causes
1.
A factor which may affect starting performance is the vehicle oil viscosity. API SG or SH rated 5W-30 motor oil is preferred for most Nissan
models. In colder weather, 5W-30 rated oil will make starting easier and maintain a more stable idle during warm-up. This is due to the lower
viscosity of 5W-30 at lower temperatures compared to 10W-30.
2.
Before installing new parts, make sure of the following:
^
Check the engine oil level. If the engine oil level is low, add oil as needed. If the engine oil level is high (above the "H" mark on the dipstick)
and the oil has a gasoline odor, change the engine oil and filter before proceeding.
^
Battery fully charged; battery cables and terminals clean and tight.
^
Fuel pump function is OK (squeeze the fuel line with your fingers and feel for pressure when the key is turned to the "on" position).
^
Compression is OK.
^
Use CONSULT to check for any related diagnostic trouble codes (e.g.: injectors, ignition system, etc.) and repair as needed.
Start Engine - Check Base Idle Speed and Ignition Timing
1.
Try to start the engine. Fully depress the accelerator during cranking.