Hyundai is no friend to cheating spouses, that's for sure. Of course, neither is Congress (despite the recent Craigslist antics of former Representative Chris Lee).

But perhaps we should start at the beginning.

'Vast defect' ?!?!?

We've gotten several notes over the past few weeks from Colorado reader Bob A, saying:

Hyundai Sonata HYBRID again delays release of HYBRID cars in U.S. - vast defect suspected - Hyundai has NO hybrid Sonata cars at U.S. dealers - what's going on?

We are usually skeptical of "vast defects," but our suspicions grew when Hyundai refused to give Sonata Hybrid sales for January. It said only that it had sold 4,792 vehicles with EPA highway ratings of 40 mpg or better, which includes the high-volume new 2011 Elantra as well as the Sonata Hybrid.

Growing suspicions

Sales of the car have begun, but Hyundai won't say how many? Even Nissan copped to selling a mere 19 of its 2011 Leaf electric cars in December, and 87 in January. Hmmmmmm.

As it turns out, there was indeed a last-minute delay, although Hyundai Motors America CEO John Krafcik says the first 2011 Sonata Hybrid was delivered by Hardin Hyundai in Anaheim, California, in January.

2011 Hyundai Elantra

2011 Hyundai Elantra

But a last-minute specification change made "amazingly late in the process," in November--with production scheduled to start in December--meant that Hyundai "ended up losing a couple of weeks of production timing," Krafcik said.

So what was this all-important change?

Making silent electric cars noisier

It was the removal of a function that allowed drivers to disable the "virtual engine sound" that the Sonata Hybrid automatically broadcasts when it switches off the actual engine in all-electric mode below roughly 12 miles per hour.

The National Highway Traffic Safety Administration (NHTSA), in its wisdom--and at the behest of politically powerful pressure group the National Federation for the Blind--is writing rules that will require all hybrid and electric cars to make noise at low speeds.

There appears to be little or no actual data that quiet hybrid or electric cars have caused additional injuries to blind or sight-impaired pedestrians. Nonetheless, the rules are coming.

Lotus Safe & Sound noisemaker

Lotus Safe & Sound noisemaker

Changes to wiring harness, software, manuals

Knowing that, and not wanting a few early Sonata Hybrids to behave differently than later models, Krafcik said the company "made the difficult choice" in November to remove the noise-disabling ability. That was a function that had been designed into the car since the beginning of the program.

This required changes to the wiring harness, the user-interface software, and even the Owner's Manual, which had already been finalized. Those changes were made in November and December.

So, all production versions of the 2011 Hyundai Sonata Hybrid will make engine noises even when their engines switch off. So much for sneaking home quietly late at night.

Europeans, who called the electric-vehicle-only mode on Toyota Prius hybrids the "cheating husband button," must be laughing their heads off.

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