As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
#2 ENGINE SLUGGISH TO START. N2 ACCELERATES TO 21-22% IN OVER 30 SEC AND DOES NOT INCREASE BEYOND THAT WITHIN THE START PARAMETERS. EGT T NORMAL DURING START. GROUNDED - YES. REMOVED AND REPLACED #2 ENGINE START VALVE REF B737-800 AMM 80-11-03. OPS CHECK GOOD. LEAK CHECK GOOD REF AMM 71-00-00-700-809-F00. ENGINE STARTS NORMAL.