1 EXHIBIT 23.3 CONSENT OF INDEPENDENT ENGINEER As an independent engineering consultant, I hereby consent to the use of my reports and data extracted therefrom (and all references to me and my Firm) incorporated by reference in or otherwise made a part of this Registration Statement on Form S-3 relating to the registration of 3,000,000 shares of the Common Stock, $0.10 par value, of Costilla Energy, Inc. W. SCOTT EPLEY, P.E. Midland, Texas January 8, 1999