What was found
ON CLIMB OUT THE #1 ENGINE FUEL FILTER BYPASS LIGHT ILLUMINATED THEN WENT OUT CONTINUED TO CLIMB AND LIGHT ILLUMINATED AGAIN. REMOVED AND REPLACED #1 ENGINE FUEL FILTER IAW B737-800 AMM 73-11-02 FROM STEP A-G, PERFORMED LEAK IAW B737-800 AMM 73-11-02 STEP H. LEAK CHECK GOOD, OPS CHECK GOOD.