Now this held true for my LS engines don't know about the coyotes, every time I did coolant flushes or changed t stats I found a lot of air would get into the system, and I would have to purge the lines by having the car on a slight incline and from cold start the car and massage or burp the upper and lower radiator lines until the t stat opened, which took about 15 mins or so, then after it opened and the level dropped I topped it off with fluid and continued to burp the lines until no bubbles came out anymore.