One problem related to engine has been reported for the 1998 Saturn SL2. The most recently reported issues are listed below.
Cracked head cylinder at 16k miles without any unusual or harsh driving. Car had to be towed to the dealer. No oil was left in the car -- it was in an "undriveable" condition. The service dept was shocked this happened on a twin overhead cam engine & thus didn't even stock the part to fix the car. Dealer also said there was no engine damage, although I find that hard to believe since the car was driven for some time without realizing the problem.