While Toyota clearly hopes the worst of its recall problems are behind it, the National Highway Traffic Safety Administration has opened a new investigation into an older Toyota vehicle.

On February 15, the NHTSA opened an investigation into 32 complaints of engine stalling in 2006 Toyota Highlander Hybrid sport-utility vehicles. Of those, 21 occurred at speeds above 40 mph, and 26 of the vehicles wouldn't restart or had to be towed to a dealership.

2006 Toyota Highlander Hybrid

2006 Toyota Highlander Hybrid

All but one of the complaints were filed in the last year, which the agency called "an apparent increasing trend." No accidents or injuries were reported.

The NHTSA summary also lists 2007 Highlander Hybrids as included in the investigation; a total of 43,941 Highlander Hybrids is being investigated. For 2008, the Highlander model was entirely redesigned, with a different engine and a revised version of Toyota's Hybrid Synergy Drive system.

An investigation is the first step in a process that can lead to a recall, if the agency determines that sufficient evidence exists to identify a mechanical or electronic fault that has caused the incidents.

2006 Toyota Highlander Hybrid

2006 Toyota Highlander Hybrid

Last August, Toyota had to recall 1.1 million Corolla and Matrix models built between 2005 and 2008 to correct a defective part that led to engine stalling. General Motors had to recall 200,000 Pontiac Vibe models for the same fault, since the Vibe used the same platform and mechanical components as the Toyota Matrix.

This is the second engine stalling concern this month. Last week, the NHTSA upgraded an investigation of fuel-pump failures on Volkswagen and Audi TDI diesel engines into an engineering investigation. That is usually the step before it orders an official recall.

[Reuters, Detroit News]

+++++++++++

Follow GreenCarReports on Facebook and Twitter.