I was wondering if anyone knew how much a motor cost for a 98 chevy malibu or would it just be cheaper to re-build it

Depending on which motor it is(3.4 or 3.8) , call the salvage yards for prices on a used one. The less miles on it, the more they cost, but used is still gonna be about 1/2 of rebuilt, which is about 1/2 of a new. If you are really set on a reman, I only recommend Mr Goodwrench rebuilts-they come with a nationwide mileage and labor guarantee that's hard to beat, and they are very competitive with the national rebuilders..

Check with your nearest auto parts store...you can usually
get a factory rebuilt engine from $800-1500

well carina suggestion next time u would like to ask a question why dont u ask a real question with specific questions such as 4 or 6 cylinder....your answer is rebuild what u have at least u know what u have take it to a machine shop and and have the heads done valve job I'm sure u r only having problems with the top end..if the car is in good shape body interior expect to pay 600-800 to have it done right....