Silhouette V6-191 3.1L VIN D TBI (1995)
Thermostatic Air Cleaner: Testing and Inspection
RESULTS OF INCORRECT THERMAL AIR CLEANER OPERATION
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Hesitation during warm-up can be caused by:
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Heat stove tube disconnected.
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Vacuum diaphragm motor inoperative (open to snorkel).
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No manifold vacuum.
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Damper door does not move.
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Missing air cleaner to TBI seal.
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Missing air cleaner cover seal or loose cover.
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Loose air cleaner.
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Lack of power, sluggish, spongy, or detonation on a hot engine can be caused by:
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Damper door does not open to outside air.
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Temperature sensor doesn't bleed off vacuum.
THERMOSTATIC AIR CLEANER CHECK
1. Inspect system to be sure all hoses and heat stove tube are connected. Check for kinked, plugged or deteriorated hoses.
2. Check for presence and condition of air cleaner to Throttle Body Injector (TBI) gasket seal.
3. With air cleaner assembly installed and engine "OFF," damper door should be open to outside air.
4. Start engine. Watch damper door in air cleaner snorkel. When engine is first started, damper door should move and close off outside air. As air
cleaner warms up, damper door should open slowly to outside air.
5. If the air cleaner fails to operate as described above, perform vacuum motor check. If it operates, the door may not be moving at the right
temperature. If the driveability problem is during warm-up, make the temperature sensor check below.
VACUUM MOTOR CHECK
1. With engine "OFF," disconnect vacuum hose at vacuum diaphragm motor.
2. Apply at least 23 kPa (7" Hg.) of vacuum to the vacuum diaphragm motor. Damper door should completely block off to outside air when vacuum
is applied. If not, check to see if linkage is hooked up correctly.
3. With vacuum still applied, trap vacuum in vacuum diaphragm motor by bending hose. Damper door should remain closed. If not, replace vacuum
diaphragm motor assembly.
(Failure of the vacuum diaphragm motor assembly is more likely to be caused from binding linkage or a corroded snorkel than from a failed
diaphragm. This should be checked first, before replacing the diaphragm motor assembly.)
4. If vacuum motor checks OK, check vacuum hoses and connections. If OK, replace the temperature sensor.
TEMPERATURE SENSOR CHECK
1. Start test with air cleaner temperature below 30°C (86°F). If engine has been run recently, remove air cleaner cover and place thermometer as
close as possible to the sensor. Let air cleaner cool until thermometer reads below 30°C (86°F) about 5 to 10 minutes. Reinstall air cleaner on
engine and continue to Step 2.
2. Start and idle engine. Damper door should move to close off outside air immediately if engine is cool enough. When damper door starts to open
the snorkel passage (in a few minutes), remove air cleaner cover and read thermometer. It must read about 55°C (131°F).
3. If the damper door is not open to outside air at temperature indicated, temperature sensor is malfunctioning and must be replaced.