Ok, I don't usually post in this forum, but I'm going to be working on friends sick 96 Cougar on Sunday, so here's the deal:
First drive of the morning/day, the "check gauges" light pops up on the dash, and he noticed that the temp was up. Seemed to happen only when sitting for a bit (like a long light, etc...). Once it is driven and the air starts flowing again, the temp drops to normal, and all is well. He says that once it does this, it won't do it again until it sits overnight and totally cools off.
I know the rad. is leaking, and that will be changed on Sun., but now I'm thinking along w/ that, the T-Stat should be changed as well. Of course as I refill, I will use the bleed off stop on the line to make sure there isn't any air in the system.
Does this sound like more than a t-stat? I shudder to think the word HG, but who knows. Up until now, it hasn't done it, so I'm thinking w/ the leaky rad, and possibly a stuck thermostat, it's letting it get a bit too hot until it unsticks and opens up like it should.
Thanks in advance,
These are highly engineered precision vehicles, the first step in diagnosing the problem is to strike the suspected offending part sharply and repeatedly with a blunt object, then re-test.