The Q45 is a full-size luxury car from Nissan's Infiniti marque. It is a rear wheel drive car powered by a V8 engine and is based on the Japan-market Nissan Cima .

1990

The first Q45 came to market in 1990. It was a distinctive automobile with no grille opening at the front and a distinctive vine-entwined logo. Styling was derivative of the innovative Audi 5000 from the 1980s. A more conventional appearance (including a grille) was added part way through this generation. Reviewers had positive comments for its performance, especially the 278 hp (207 kW) 4.5 L VH45DE engine and 4-wheel multilink independent suspension. Sales were hampered by a notorious advertising campaign which did not include actual photos or information about the car. In Japan, this model was later sold under the name of Nissan Infiniti Q45 rather than Cima.

1997

The Q45 was refreshed in 1997 with a more conventional appearance, and a smaller 4.1 L VH41DE engine that produced 267 hp (199 kW). From this model the Q45 for North American market and the Cima for Japanese market were unified. The suspension (struts in front and multilink in the rear) had been tuned more for comfort, which did nothing to help the car's sales. The appearance was changed to be even more conventional for 1999, and high-intensity discharge (HID) headlights were added.

2002

The Q45 came back completely redesigned for 2002. This rear-wheel-drive vehicle focused on performance again with a new 340 hp (253 kW) 4.5 L VK45DE V8, machine-gun style HID headlights, and sharper styling. The car features a 5-speed automatic transmission with overdrive. Despite good reviews, sales remained poor.

The current model Q45 has received praise from Car and Driver, Edmunds and Consumer Guide. Low sales are attributed not to the car’s overall quality or performance, but to lack of advertising.

The Q45 received a number of upgrades for the 2005 model year, including new front and rear fascias, restyled hood and grille, restyled trunk lid, new headlight design, integrated fog lights and LED taillights. Inside are new sport contour double-stitched seats, white luminescent gauge markings, chrome accents and dark maple trim. 2005 upgrades include a recalibrated transmission and a new 17 in wheel design.

The following features are standard in the Q45: all-leather interior, power sunroof, 8-way power front seats, remote keyless entry, rain-detecting wipers and side curtain airbags. Standard electronics include: CD, 8 Bose speakers, trip computer, rear camera parking sensors and a voice-activated navigation system. The 2002 Q45 was the first vehicle to ever offer voice-activated navigation controls.

The car seats five and has a base price of US$56,200.