Heading for a bumpy road? Married at First Sight newlyweds Tom and Lillian get into a heated discussion about cars after having sex for the first time in the Tuesday, August 16, episode, as seen in Us Weekly's exclusive sneak peek.

The FYI unscripted series' preview clip shows the pair getting to know each other in bed, with Tom, 28, still unsure about when to tell his new bride, 24, about his unusual housing situation.

"Tonight was a very nice night, very romantic," Tom says to the camera. "But also, I'm nervous to open up to her because I'm not sure if she really is going to accept me for me, and that's why I still haven't told Lily that I live in a bus. She has no idea — I don't know when I'm going to tell her this because if she hates the bus, that is going to be a problem."

The yacht interior specialist attempts to broach the topic by telling his realtor wife that he is "truly a minimalist," but she misreads the comment and thinks he is criticizing her new set of wheels.

"I feel like I've earned everything that I have because I work for it, and it's not fair for you to just generalize, 'Oh, people that drive new cars …' and what not," Lillian tells the camera. "It annoyed me very much — it struck a nerve because we just consummated our marriage last night, and I have feelings for him, and I'm not a materialistic person."

Watch the tense clip in the video above. 

Married at First Sight, produced by Kinetic Content, airs on FYI Tuesdays at 8:30 p.m. ET. 

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