I have a 01 PSD Excursion that is only used to tow my 28ft trailer. I towed to the track in the morning normal start no problem. After racing all day I jump back in it and had a hard time starting it. I clicked the key and waited for the light on the dash to go out and started cranking it over with no start. I cycled the key again and it just cranked. Did it one last time and it started. After getting home and unpacking I got back in the truck and took it for a drive and it started with no issue. This is the first time this has happened. Is there a way check the glow plugs? Or something else I should be looking at? I usually tow a few hours and don’t want to get stranded. Thanks in advance.

Bob