Cadillac 1999 DeVille Owner's Manual page 288

Follow these steps to reinstall the air cleaner assembly:
1. Slide the air cleaner lid into the slots in the front
edge of the air cleaner base.
2. Pivot the air cleaner cover and the air duct assembly
downward. Make sure that both latches are secure
and fully engaged.
3. Reinstall the clean air duct over the mass airflow
sensor. Make sure that the duct is secure around the
entire outer edge of the sensor.
4. Tighten the air duct clamp.
5. Reconnect the IAT sensor.
Refer to the Maintenance Schedule to determine when to
replace the air filter.
See "Scheduled Maintenance Services" in the
Maintenance Schedule booklet.
6-18
CAUTION:
Operating the engine with the air cleaner/filter
off can cause you or others to be burned. The air
cleaner not only cleans the air, it stops flame if
the engine backfires. If it isn't there, and the
engine backfires, you could be burned. Don't
drive with it off, and be careful working on the
engine with the air cleaner/filter off.
NOTICE:
If the air cleaner/filter is off, a backfire can cause
a damaging engine fire. And, dirt can easily get
into your engine, which will damage it. Always
have the air cleaner/filter in place when
you're driving.
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