CNA National Warranty CNA does not honor their auto warranty contracts Internet

Purchased an extended warranty a couple of years ago. My engine blew up about a month ago and CNA refuses to cover it under the warranty. The service repair shop said it was due to a thermostat malfunction. CNA said they tested the thermostat one time and it worked. They also said the problem was a faulty hose (which is not covered under the warranty). The service repair shop said the hose and hose clamp are perfectly OK and that sometimes thermostats fail intermittenly. CNA changed from blaming the hose, then the hose clamp, to blaming the radiator cap. They said the cap should have releived the pressure and that caps are not covered either. The service repair shop says there is nothing that isn't covered under the warranty that could have caused the problem. I'm out about $8,000 plus the cost of the warranty. Do not think that because you have an extended warranty you will be reimbursed if your engine blows up.