Altima SE L4-2.4L (KA24DE) (1997)
Receiver Dryer: Customer Interest
A/C - Poor Performance, Suction Side Shows Low or Vacuum
Classification:
HA97-002a
Reference:
NTB97-007a
Date:
January 15, 1998
Subject:
1993-97 ALTIMA POOR AIR CONDITIONING (A/C) PERFORMANCE-LOW PRESSURE GOES INTO VACUUM
APPLIED VEHICLE:
1993-97 Altima (U13)
APPLIED VIN:
Vehicle built before 1N4BU31D*VC138483
APPLIED DATE:
All vehicles built through June 11, 1996
SERVICE INFORMATION
If a 1993-97 Altima vehicle has poor air conditioning system performance, there may be two causes.
1.
An evaporator core with an internal bypass condition. This condition causes refrigerant to flow from the expansion valve directly to the low side
hose without going through the heat-exchange portion of the evaporator core itself. This incident is identified by lower than normal high side
pressures and low side pressures going very low or going into vacuum. There will also be frost on the pipe from the evaporator to the compressor.
In this case you must replace the evaporator assembly.
2.
Loose desiccant from the liquid tank which plugs the expansion valve. This incident is identified by lower than normal high side pressures and low
side pressures going very low or going into vacuum.
In this case you must replace the following components at the same time:
^
Liquid tank
^
High cooler pipe "A"
^
High cooler pipe "B"
^
Evaporator inlet tube
^
Expansion valve.
The high/low side pressures are similar. The best method to identify the evaporator incident from the loose desiccant incident is that the pipe from the
evaporator outlet to the compressor inlet is heavily frosted in the evaporator incident.
SERVICE PROCEDURE
1.
Connect an ACR4 machine (or set of suitable gauges) to the vehicle service ports.
2.
Conduct A/C system performance and operational testing. Refer to page HA-32, DIAGNOSES - Overall System, Performance Chart in the 1993
service manual. Refer to the HA section under TROUBLE DIAGNOSIS, Performance Chart in the 1994-97 service manuals. Make sure you use
the correct chart for the manual or automatic A/C system.