occasional rattle noise when starting

2006 BUICK LA CROSSE
86,000 MILES • RWD • AUTOMATIC
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JOAN A. CASWALL
  • MEMBER
  • 1 POST
The rattle noise the first time sounded like several tin cars banging together. Sound seemed to have come under the seat of driver side. Turn off engine. No problem lights were showing. Turned on the engine again and there no noise and it runs just fine. This happened again recently but the sound was not as loud. It goes away immediately. No trouble engine lights were lit.
thank you.
Aug 11, 2017 at 8:39 PM
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STEVE W.
  • ✓ASE Certified Mechanic
  • 15,200 POSTS
  • ASE Certified Mechanic
That sounds like a loose heat shield on the converter. With everything cold go under and tap on the shield and see if it has broken/rusted loose. If it has you can either just ignore it or have it tack welded back in place.
Aug 13, 2017 at 11:29 AM
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