Pontiac Fiero 1988 Service Manual page 31

1A-0 HEATING AND VENTILATION
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C H E C K V E H I C L E FOR
C O L D AIR L E A K S AT DASH,
HEATER C A S E S AND FROM
V E N T S . C H E C K
UNDERSEAT FOR
O B S T R U C T I O N S
WITH T H E IGNITION SWITCH OFF, MOVE
T H E T E M P E R A T U R E L E V E R TO F U L L
C O L D T H E N RAPIDLY TO F U L L HOT. LIS-
TEN F O R DOOR SLAM PRIOR TO THE END
O F C O N T R O L L E V E R TRAVEL.
I
NO DOOR SLAM
NONE FOUND
DOOR SLAM OK
C H E C K T H E T E M P E R A -
T U R E DOOR ADJUSTMENT,
C A B L E S , LINKAGE AND AD-
J U S T TO F U L L HOT. C H E C K
FOR F U L L C O L D .
WITH T H E T E M P E R A T U R E
DOOR F U L L HOT, START THE
V E H I C L E . C H E C K THE T E M P E R -
ATURE O F T H E HEATER INLET
AND O U T L E T H O S E S BY F E E L .
THE AIR T E M P E R A T U R E
AROUND T H E H O S E S MUST B E
AT L E A S T 85°F.
HOT INLET & WARM O U T L E T
WITH THE BLOWER ON
HIGH, MOVE T H E TEMP-
ERATURE L E V E R FROM
FULL HOT TO F U L L
C O L D AND LISTEN FOR
AIRFLOW CHANGE.
NO AIRFLOW
CHANGE
BOTH WARM
C H E C K THE THERMOSTAT
FOR P R O P E R
INSTALLATION AND
P R O P E R L Y S E A T E D .
L
R E M O V E THE H O S E S AT THE
HEATER C O R E & C H E C K FOR
P R O P E R INSTALLATION
( R E F E R TO MANUAL FOR
H O S E ROUTING).
AIRFLOW C H A N G E
C H E C K THE TEMPER-
A T U R E DOOR AD-
JUSTMENT, C A B L E S ,
CONTROL, LINKAGE &
ADJUST TO F U L L HOT.
NOT OK
OK
OK
REINSTALL
& R E C H E C K
R E P L A C E
THERMOSTAT
R E V E R S E D C H E C K FOR S Y S T E M
OBSTRUCTION
B E T W E E N THE
BLOWER & THE
S Y S T E M O U T L E T S .
BACK F L U S H HEATER
C O R E , DRAIN ENTIRE
COOLANT & R E P L A C E .
R E T E S T .
INSTALL P R O P E R L Y
& R E T E S T
BOTH H O S E S
WARM
HOT INLET & WARM
O U T L E T H O S E S
R E P L A C E HEATER C O R E . S Y S T E M OK
G 2 0 0 1 8 1 A
Figure 7 Insufficient Heating or Defrosting Diagnosis Procedure (2 of 2)