China started implementing a public transport priority policy in 2004 to encourage people to use public transit, especially buses, and reduce reliance on private cars. This paper used 334 questionnaire survey data from Changzhou City, China, and explored the moderating role of bus satisfaction based on the examination of the antecedents and consequences of affective motivation for private cars through two studies. Study 1 explored the antecedents of affective motivation for private cars and the moderating effect of bus satisfaction. The empirical results revealed that instrumental motivation is the most relevant predictor of affective motivation favoring private cars, followed by symbolic motivation. The moderating effect of bus satisfaction on the relationship between symbolic motivation and affective motivation was significantly negative. Study 2 explored the consequences of affective motivation for private cars and the moderating effect of bus satisfaction. Empirical results indicate that decisions regarding private car ownership and use are significantly negatively influenced by bus satisfaction. Bus satisfaction has a significantly positive moderating effect on the relationship between affective motivation and private car ownership and use. The marginal effect of bus satisfaction on the probability of simultaneously owning and using private cars is significantly negative, and it strengthens the influence of affective motivation in promoting both ownership and use of private cars. These results demonstrate that for individuals with experience using both buses and private cars, the public transport priority policy focused on improving bus service quality can effectively reduce private car ownership and use. These results can serve as evidence to support policymakers in continuing to enhance the public transport priority policy.