2004 Buick LeSabre Owner's Manual - Page 258

{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 helps to stop flame if the engine backfires. If it is not there and the engine backfires, you could be burned. Do not 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. 5. Inspect or replace the engine air cleaner/filter. 6. Reinstall the rear section of the engine air cleaner/filter housing. 7. Reconnect the electrical connector. 8. Reattach the air intake hose by snapping it back onto the throttle body. 9. Refasten the latches to the engine air cleaner/filter housing cover. 5-20