1992 Mazda B2200 2.2L mileage: 108,000. In the mornings and in cold weather it tends to hesitate or miss between 50 and 60 MPH until it gets hot. Wires, plugs, caps, rotor, module and coil have been replaced. I'm an experienced mechanic, so I did a compression test, pulled the head off and reground the valves, and rebuilt the carburetor. I even replaced all the electronic sensors including the one that screws into the bottom of the radiator, which is known to fail on these trucks. Is there something that I have overlooked or is this a quirk that I have to live with?