Heater - Reduced System Performance
90chevy17Number: 90-152-1A
Section: 1A
Date: January 1990
Corp. Bulletin No.: 931106
Subject: REDUCED HEATER SYSTEM PERFORMANCE
Model and Year: 1990 W CARS
Comments on the above vehicles about heater system performance such as being slow to warm up or inadequate heat may be received from some customers.
If the heater system is operating properly and the engine temperature is in the operating range, the cause of the condition may be reduced air/heat distribution from the heater outlet.
This condition may now be addressed by using the following service parts and procedures.
The parts and procedures for the W Car without the performance audio system are as follows:
PARTS
QTY. PART NO. PART NAME
1 52452131 Heater Outlet Duct
26 in. *06375 3M # 4508 Scotchfoam Black Vinyl Foam Tape
* Purchase Locally
Parts are currently available from GMSPO.
PROCEDURE:
Figure 3:
* Remove the R.H. hush panel, see Figure 3.
Figure 1:
* Remove the adapter duct, see Figure 1.
* Remove the heater outlet duct, see Figure 1.
Figure 2:
^ Remove the two top screws from the module, one on each side. These two screws will be used to mount the new heater outlet duct, see Figure 2.
^ Install the 1/8 X 3/4 in. foam tape to the grooved mounting surface of the new heater outlet duct, approximately 11-3/4 in. of tape across the top of the outlet duct and 7 in. of tape on each side. Trim off excess tape.
^ Install the new heater outlet duct to the module, see Figure 2.
Figure 1:
^ Install the adapter duct, see Figure 1.
Figure 3:
^ Cut off a two inch square piece of the R.H. hush panel as indicated in Figure 3. This may be done with a saw blade or a bench grinder.
^ Install the R.H. hush panel.
Labor Operation Number: T1510
Labor Time: 0.4