A/C - Insufficient Heater Performance

File In Section: 1 - HVAC

Bulletin No.: 73-11-04

Date: January, 1998

Subject:
Insufficient Heater Performance in Extreme Cold Weather (Replace HVAC Heater Core and Floor Outlet Duct)

Models:
1997 Chevrolet Venture
1997 Oldsmobile Silhouette
1997 Pontiac Trans Sport

Condition

Some owners may comment on insufficient heater performance in extreme cold weather conditions.

Cause

Condition may be due to insufficient heater core and air flow capacity.

Correction

Replace the HVAC heater core and air distribution floor outlet duct following the procedure in Section 1B of the Service Manual and perform the following procedure. Also, inspect and repair any air flow obstructions under the front seats for the rear floor heater ducts (i.e.: power seat wiring or personal items).

Procedure





Numbers below in parenthesis refer to callouts in Figure 1.

1. Remove heater inlet nipple following the procedure in Section 1B of the Service Manual.

2. Using an "O" ring remover tool or other suitable tool, remove the rubber flow restrictor (4) from the male end of the heater nipple and discard (Figure 1).

3. Using care not to damage the "O" ring (2), enlarge the opening of the spacer (3) as large as possible with a knife or other suitable tool from the male end of the heater nipple (Figure 1).

4. Reinstall heater inlet nipple following the procedure in Section 1B of the Service Manual.

5. Refill the cooling system following the procedure in Section 6B of the Service Manual.

Parts Information

P/N Description

52481472 Core, Heater
52470410 Duct, Air Distribution Outlet (Floor)

Parts are currently available from GMSPO.

Warranty Information





For vehicles repaired under warranty, use the table.