Behind the Wheel with Phil Lebeau

Lexus, Infiniti get rare 'not recommended' reviews

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Lexus and Infiniti, two Japanese luxury brands with well-established reputations for quality vehicles, have received an unflattering designation from Consumer Reports (CR).

The auto team at Consumer Reports has said it cannot recommend the Lexus IS 250 and Infiniti Q50 after both placed among the lowest in rankings of luxury sedans.

2014 Lexus IS 250
Source: Toyota Motors

In describing the Q50, Jake Fisher, director of automotive testing for Consumer Reports said "this car seems to have lost its way." As for the Lexus IS 250, Consumer Reports said, the sedan "scored too low to be recommended."

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Consumer Reports recommends vehicles that perform well in a series of tests and have average or better reliability in the organization's annual auto survey of vehicle owners. How models perform in government crash tests is another factor considered when vehicles are recommended.

CR pans Lexus road test

Consumer Reports editors gave a harsh review of the Lexus IS 250 saying, "It was the worst road test score posted by any Lexus sedan in recent memory."

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While the sedan was given an overall rating of "good", CR panned the car's performance.

"The Lexus IS handling is short on finesse, with vague-feeling steering that doesn't telegraph much feedback. Road noise is elevated and the ride is neither plush nor tied-down," it said. "[The IS 250] acceleration lacks punch. Fuel economy is disappointing at 21 mpg overall in CR's own tests," it added.

A Lexus spokesperson responded to the report said, "Lexus is unclear on the cause for the low rating. We look forward to engaging in a discussion with them to get more direct feedback on their experience with the car. The 2014 IS sedan is resonating extremely well with customers, automotive and other non-automotive publications."

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Road tests highlight issues

Consumer Reports said the Inifiniti Q50 did very good in the CR road tests. Still, the sedan ranked below competitors due to a number of issues the magazine editors found with the car.

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Consumer Reports said, "The Q50 isn't as much fun to drive as the G37. Handling is mundane, due in part to dull steering. The underwhelming driving experience strips the car of much of its sporty legacy."

The CR auto team did praise the Q50 as "very quick, even with the added weight of the optional all-wheel-drive system."

A spokesperson for Infiniti said, "despite scoring well, the Q50 is still too new for their (Consumer Reports) reliability results, which is necessary to categorize the car as 'Recommended.' We're confident that when those results are in, the Q50 will be on the 'Recommended' list."

—By CNBC's Phil LeBeau. Follow him on Twitter @LeBeauCarNews.

Questions? Comments? BehindTheWheel@cnbc.com.