has anybody else had this happen? Yesterday (Sat) truck acted like it would not get out of its own way (sunny and mid to upper fifties). but today after sunset mid to upper forties, truck runs like a scalded dog. Did nothing to it from incident to incident, cept park her. Recently had a new gas station open up and has gas for $2.87 a gal causing the others in the same area to drop from 2.99 to "compete". The way she was acting Sat I was thinking poor fuel Sun however, she acted like she was drinking aviation fuel - still had an audible "ping" but run, man she was a screamer. any thoughts.