Saturn Corp. is recalling 1,800 cars because an antifreeze blended in Houston by Texaco Refining and Marketing is corroding their cooling systems.

The General Motors subsidiary has sent letters to owners of affected Saturns, asking them to take their cars back to their dealers to exchange them.Company officials said 1,836 Saturn cars built at the company's Spring Hill, Tenn., plant between March 25 and April 4 had an overly caustic coolant mixture in their cooling systems.

Officials at Texaco Refining, a subsidiary of Texaco Inc., said the problem was a blending accident.