Acura RDX TB4

The third-generation RDX (TB4, 2019 onward) returned to turbocharging and positioned itself as Acura's volume SUV in the premium compact class. This grounding data lists the drivetrain as Honda's L15B, the 1.5-liter VTEC turbo found in nearly every model in the lineup since 2016. As the company's most important downsizing engine it is technically mature, but it carries a characteristic cold-climate problem you need to understand before buying.

The best-known issue on the L15B is fuel dilution: frequent short trips in cold weather let fuel enter the engine oil, thinning the lubricating film and accelerating wear — a problem that led to a class action and extended warranty coverage. Alongside that come intake-valve deposits from direct injection, a rattling charge-air actuator, and in more serious cases a leaking head gasket between cylinders two and three. There is also a fuel-pump recall (NHTSA 23V-858, model years 2018–2020) whose completion should be documented. Drivers who cover a lot of short-trip miles should change oil more often and keep an eye on the level.

Around the drivetrain, the TB4 accumulates safety- and comfort-related issues. The rear window can shatter spontaneously with no external impact (TSB 22-014, though not a formal recall), and in salt-belt regions corroded rear coil springs break, which can damage tires or brake lines. The touchpad infotainment freezes regularly — a $10.5 million settlement covered the 2019/2020 model years. More serious are the collision-mitigation braking system (CMBS) grabbing hard without cause beside trucks or guardrails, and a limp mode with significant power loss that shuts down climate control and infotainment. Add loudly squealing brakes and creaking from the panoramic roof.

The recommendation: the TB4 is a modern, good-driving premium SUV whose engine is durable with adjusted maintenance. Before buying, make sure the recalls are cleared, inspect the rear window and — in salt regions — the rear springs, and test the behavior of the driver-assist systems. An example from a milder climate with a clean recall history is far less trouble than a salt-worn short-trip car.