Acura planned to debut its RLX Hybrid sedan in spring 2014.

But spring came and went, and as of midsummer the car still is not available for purchase in the U.S.

Rumors abound about the RLX Hybrid’s delay, but Mike Accavitti, senior vice president and general manager of Acura in the U.S., is tight-lipped, saying the car isn’t on sale yet due to a “technical” issue.

“I can tell you that it just hasn’t met with our expectations yet,” he tells WardsAuto in a recent phone interview.

Purported reasons for the car’s delay range from a lithium-ion-battery shortage to engineers needing to work out the kinks of the car’s 3-electric-motor Super-Handling All-Wheel-Drive system.

The RLX’s powertrain setup is similar to that in the future NSX supercar, a prototype of which went up in flames last month while undergoing testing on Germany’s Nurburgring track. However, the RLX Hybrid has a more modest output than the NSX, requiring less cooling.

The RLX Hybrid will make 377 hp via its powertrain: three electric motors paired to a 3.5L direct-injected V-6. The NSX is expected to make more than 500 hp from a mid-mounted V-6 with twin turbochargers mated to three electric motors.

Accavitti expects RLX Hybrid sales to commence relatively soon, noting some units were on a boat from Japan in late July.

“They should be arriving here within the next month or so, and hopefully they’ll get to dealerships soon after that,” he says.

While the RLX Hybrid is expected to be a niche vehicle for Acura, Accavitti says the unique 3-motor/AWD technology under its hood lends cachet, and the Honda near-luxury brand is “looking forward to getting that in the marketplace as soon as we can.”

For the past year, Acura’s U.S. dealers have had only the front-wheel-drive non-hybrid RLX flagship sedan to sell. Volume, while up through July, is a fraction of what the segment’s top sellers racked up.

From January through last month, RLX deliveries rose 7.1% over the same period year-ago, to 2,285 units.

The Mercedes E-Class and BMW 5-Series sold 41,244 and 33,293 units, respectively, in the first seven months. The totals made the German cars the No.1 and No.2 top-selling models through July in WardsAuto’s Middle Luxury Car segment.

However, the RLX is performing better than its predecessor, the RL, did in its final years.

From 2009 through 2012, RL sales ranged from a peak of 2,043 to a low of 379.

The second-generation RL’s best volume, 17,572 units, was in 2005, the car’s first full year of sale.

Accavitti says Acura has plans to boost FWD RLX sales but won’t go into detail.

“That’s a real difficult segment to compete in,” he says. “We’re never really satisfied with our sales rate. I’m not. I think we can always do better.”

cschweinsberg@wardsauto.com