Ford Motor Co. will be in court this week to defend itself against a $3-billion consumer class-action suit, described as the largest ever against a U.S. auto maker. Ford is being sued by California consumers who claim the company failed to disclose information about an allegedly faulty ignition part installed in 22 million Ford vehicles nationwide. The part is suspected of causing vehicles to stall. It is one of six suits filed as consumer class actions against the world's No. 2 auto maker. The trial, set to begin Wednesday in Alameda County Superior Court in Oakland, could lead to the first court-mandated recall in the history of the automobile industry. Attorneys for plaintiffs in the six separate cases are seeking damages totaling $6.5 billion, or more than a third of Ford's 1998 net income. Ford says the part at issue, which was used to regulate the electrical current, hasn't been used by Ford since 1995. The suit was filed in 1996 on behalf of more than 3 million Californians who either purchased and sold 1983 to 1995 model Ford, Lincoln and Mercury vehicles or currently lease or own them. The plaintiffs are not seeking damages because of any deaths or injuries linked to the part. Rather they are suing Ford for its alleged violation of state laws that prohibit false advertising and unlawful business practices.