Toyota's announcement of
plans to recall 270,000 of its V8 and V6 models, including a number of
Lexus sedans, was a little light on information. The company didn't say much about the issue other than faulty valve springs could cause a vehicle's engine to stall while driving. Fortunately, the same anonymous source that came through with some information during
Toyota's recent pedal recall crisis has stepped up to fill-in some of the blanks.
Apparently, Lexus dealers have been encountering
the defect for a few years. The fault typically manifests itself as a zig-zag break about three-quarters up the valve spring. This means that typically, the spring still has enough tension to keep the valve retainers in place, preventing the valve itself from going all hari-kari on the cylinder, cylinder wall and head.
That's not always the case, though. If the failure happens at high RPM, the valve can come loose, causing significant damage to the engine. According to our source, one
Lexus GS350 incurred $12,000 worth of damage (in parts alone) during such an incident. And there's no word on who footed the bill.
Toyota hasn't said exactly what's caused the issue, though our source indicates that a Field Technical Specialist within the automaker believe the bad springs either have a manufacturing issue or a deep scratch – weak points that allow the part to fail prematurely. As for why the issue effects both the company's 3.5-liter V6 and 4.6-liter V8, we're assuming that both engines use the same valve springs.