GM Service Manual Online
For 1990-2009 cars only

REDUCED A/C PERFORMANCE REPLACE LIQUID LINES

Subject: REDUCED AIR CONDITIONING PERFORMANCE

Model and Year: 1991 CAPRICE

Application: 1991 "B" Styles between VIN Breakpoints Below MR124639 To MR149912 MW234399 To MW258877

Condition: Some vehicles built between the above listed VIN breakpoints may exhibit reduced A/C performance. This condition will be indicated by a 10 degree temperature increase at the center duct and a low side pressure that will not reach the 24 PSIG compressor cycle "off" point.

Cause: The liquid line may be oversized at the location of the orifice tube, allowing refrigerant to "bypass" the orifice tube.

Correction: The technician should perform the "poor performance diagnostics" as outlined in the Service Manual. If the performance is not improved when following the guidelines, Replace the Liquid Line.

Labor Operation Number: D3083 Use applicable labor time guide for labor hours. Note: Time includes recover/recharge A/C system.

General Motors bulletins are intended for use by professional technicians, not a "do-it-yourselfer". They are written to inform those technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions and know-how to do a job properly and safely. If a condition is described, do not assume that the bulletin applies to your vehicle, or that your vehicle will have that condition. See a General Motors dealer servicing your brand of General Motors vehicle for information on whether your vehicle may benefit from the information.