For 1990-2009 cars

# AIR CONDITIONING ORIFICE TUBE RELOCATION

#### VEHICLES AFFECTED: 1986 'A', 'E' and 'K' Series

On 1986 'A' series, the air conditioning orifice tube was moved from the inlet of the evaporator (1985 models) to the connection at the condenser. (Figure 1). The orifice tube can be viewed through the grill. The orifice tube was relocated to eliminate the hissing sound which was objectionable to some owners.

Some technicians have not been aware of this relocation and have installed another orifice tube back at the evaporator. This obviously will severely reduce cooling. To check for the orifice tube by the condenser, feel the liquid line, it should be cold when the air conditioning is in operation.

For the 1986 'E' and 'K' series the orifice tube is in a short section of tube between the low side temperature sensor and the high side temperature sensor. (Figure 2). It is not in the evaporator inlet tube.

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.