Electronic word-of-mouth (eWOM) has become an invaluable information source for consumers to make purchase decisions and is highly valued by companies. Extensive studies have explored how eWOM affects sales; however, the results are inconsistent. To reconcile these mixed findings, we leverage signaling theory. From the signaling perspective, product signals may attenuate or strengthen the influence of eWOM on product sales. Focusing on the automotive industry, a typical domain of high-involvement products, we investigate the moderating effects of three critical product signals (i.e., price, brand origin, and the number of customers) on the relationship between eWOM and car sales using a panel dataset collected from a leading eWOM platform. The results show that the awareness effect of eWOM on high-involvement product sales is more influential when (1) the product price is lower, (2) the product has a larger number of customers, and (3) the product belongs to foreign brands. These findings contribute to the literature and help business practitioners better understand the impact of eWOM on sales in the context of high-involvement products.