A two-day shutdown last week at General Motors' Oklahoma City assembly plant was caused by an engine stalling problem, according to the union that represents the plant's workers.
The plant builds the Chevrolet Malibu and Oldsmobile Cutlass. GM had just started building 1998 models when the stalling problem surfaced July 18. It affected cars with 3.1-liter V-6 engines.
Workers found that the V-6 quit running when the car reached 20 mph, said Yvonne Smith, vice president of UAW Local 1999, which represents workers at the plant.
The problem prompted the plant to be shut down last Monday, July 21, and Tuesday, Smith said, while engineers tried to find the problem. Production resumed Wednesday.
The problem was traced to an error in the software loaded in the engine's powertrain control module, Smith said. New software will be installed in the control modules to fix the problem.
A GM Powertrain spokesman last Thursday declined to give details of the cause of the two-day shutdown.
None of the suspect vehicles were shipped to dealers. 'Our lots are full-up here with cars,' Smith said.
The Oklahoma City plant has been building the cars at a rate of 65 units per hour on a single shift. The two-day shutdown cost at least 1,040 units of production.
It was the second unplanned shutdown at Oklahoma City this year. UAW workers staged a seven-week strike in April and May.
The cars' V-6 engine, dubbed the L82, is built at a GM Powertrain plant in Canada. The powertrain control modules are supplied by Delphi Automotive Systems, GM's parts making unit.
Chevrolet Malibus are also built at a GM plant in Wilmington, Del., but that plant was not shut down.