Intermittent undercarriage rattle

2011 KIA SPORTAGE

112,000 MILES • 4 CYL • 2WD • AUTOMATIC

AHAIGHT

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Usually after about twenty minutes of driving if I idle at a stop light there's a really aggressive, loud rattle in the undercarriage, not really side specific. a friend suggested it sounded like when her heat plate was loose. but a recent trip to the mechanic said there was nothing wrong. Also starting to notice a metallic rattle in the steering column.

Jun 8, 2019 at 3:43 PM

JACOBANDNICKOLAS

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110,175 POSTS

Welcome to 2CarPros.

Does the noise go away when you press the gas? Also, although the heat shields may be good, there is a chance that the catalytic converter may have come apart internally. That isn't something you can see.

Try this, take a rubber mallet and tap on the exhaust system in all different places to see if you can recreate the noise. Do that and let me know what you find. I attached a few pics to help you identify the catalytic converter. The locations shown are either under the vehicle or in the back of the engine off the exhaust manifold. It is based on production dates.

Let me know if this helps or if you have other questions.

Joe

Images (Click to enlarge)

Jun 8, 2019 at 9:54 PM

AHAIGHT

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2 POSTS

Thanks! Once the rain lets up I'll go under there. The noise does stop when I press the gas!

Jun 14, 2019 at 3:31 AM

JACOBANDNICKOLAS

CERTIFIED EXPERT
110,175 POSTS

Welcome back:

My first guess is either a heat shield or the converter is loose internally. Let me know what you find.

Joe

Jun 14, 2019 at 7:12 PM