My blower starts fine. After it is warm, I depress accelerator and it stutters and losses power. After it has warmed up for 10-15 minutes, it works ok. I've cleaned the air filter (not very dirty); I removed the spark arrestor screen to clean it (not clogged). Now, I want to remove the spark plug and check that. It is at an odd angle and I can't get a good grip around it; any suggestions???