No I didn't replace the hoses except for a few short ones. I bought some aftermarket hoses and I was apalled at how bad they were-you couldn't even use them.By a bad hose, you mean hoses that collapse and block coolant flow?

Unfortunately I think my problem is head gasket related.I noticed some very fine bubbles coming up to the radiator neck with the cap off . This might be from combustion pressure blowing into the water jacket ): . Also one of the plugs looks cleaner than the other 3 which could be a sign of some water in the cyl.There's none of the obvious blown headgasket signs though.I could try pulling a plug lead to see if the bubbles stop.

I'm gonna try retourqeing the head.If that doesn't work its a leak down test and a combustion leak test(chemical that tests coolant for carbon monoxide).

Funny, I was just driving my car at night here and it ran fine on the highway with the AC on, but this afternoon it ran warm in the 93 degree heat...