For 1990-2009 cars

# A/C NOT COOLING AT IDLE POOR CONDEN. CORE AIR FLOW

INSUFFICIENT AIR CONDITIONING COOLING DURING IDLE/SLOW MOVING TRAFFIC CONDITIONS OR ON STEEP GRADES IN HOT AMBIENT TEMPERATURES

1985-86 NINETY-EIGHT AND 1986 TORONADO AND DELTA 88

This bulletin supersedes Dealer Technical Bulletin 86-T-37 dated June 9,1986.

When a 1985 or 1986 model car listed above is operated at high ambient temperatures with the air conditioning on and under operating conditions such as driving up long, steep highway grades, idling the engine, or driving in congested city traffic, the driver may experience intermittent reduced air conditioning performance.

This reduced air conditioning performance may be the result of insufficient air flow through the condenser core. To improve this air flow, a new coolant fan air conditioning pressure switch, with lower turn-on pressure, went into production effective with the following serial numbers:

Assembly Plant Plant Code VIN Breakpoint -------------- ---------- -------------- Delta 88 Wentzville 1 Start of Production Willow Run W GW307568

Ninety-Eight Lake Orion 4 G4317393 Wentzville 1 G1312436

Toronado Hamtramack U GU308905

To repair this condition on vehicies built before the breakpoints listed, replace the coolant fan air conditioning pressure switch with part number 25527510 (black plastic case).

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.