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What: Shares of car safety equipment maker Autoliv (NYSE:ALV) sank 10% today after its quarterly results and guidance missed Wall Street expectations.

So what: Autoliv shares have rallied over the past few months on healthy North American auto sales, but today's wide third-quarter miss -- pre-tax earnings of $175 million versus the consensus of $182 million -- coupled with downbeat full-year guidance is forcing analysts to lower their valuation estimates. Continued weakness in Europe and slowing demand from China weighed particularly heavily on sales, reigniting serious concerns over Autoliv's exposure abroad.

Now what: Autoliv now sees organic sales growth of 4.5% and an operating profit margin of roughly 9.5%, below its prior view of 6% and 10%, respectively. "Due to the uncertain market conditions in Europe, it is still unclear how long the holiday shutdowns will be this year among the vehicle manufacturers," management cautioned . "Consequently, our sales and margin guidance is more uncertain than usual." With the stock now off about 20% from its 52-week highs and trading at a single-digit forward P/E, however, much of that uncertainty might already be baked into the price.

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Fool contributor Brian Pacampara has no positions in the stocks mentioned above. The Motley Fool has no positions in the stocks mentioned above. Motley Fool newsletter services recommend Autoliv. Try any of our Foolish newsletter services free for 30 days. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.