CHRYSLER <C> RENAULT DELAY AM MOTORS <AMO> PACT Chrysler Corp and Regie Natiionale des Usines Renault said they agreed to extend by up to two weeks the period for reaching definitive agreement on Chrysler's proposed 1.5 billion dlr takeover of American Motors Corp. The letter of intent signed by Chrysler and Renault on March nine set April nine as the target date for completing negotiations. However, the letter also allowed room for an extension of that date to April 23 if an agreement could not be reached. The two companies said they "now plan to complete work by April 23." Chrysler and Renault said, "Given the complex nature of the deal, the need for additional time was to be expected." The March letter of intent between the two companies says that Chrysler could ask Renault to extend the agreement date "in the event that prior to April 9, 1987, Chrysler discovers an unforeseen problem in the course of its 'due diligence' investigation of the company," referring to American Motors. A Chrysler spokeswoman would not say whether some problem had cropped up in the talks. She stuck by the company's statement that more time was needed because the talks are complex. "That is our definition of the delay," she said. Under the previous agreement between Chrysler and Renault, their letter of intent would be terminated on April nine or when an agreement was reached. But the letter could be amendend by a written agreement by both companies. The Chrysler spokeswoman said, "We are still working toward a definitive agreement." Said another Chrysler official who is not part of the talks but who would be told if the deal were in trouble: "There are no glitches." Analysts also downplayed the significance of the delay. "I can't visualize where they wouldn't want it to be done," said Donaldson Lufkin Jenrette analyst Richard Henderson.