I have a 94 Ranger 4 cylinder, 5 speed, that smokes bad when I first start it but won't do it if I park facing downhill unless it is really cold. If it is warm it will do it if I park level or uphill. The smoke is white and seems to be steam but I am not sure. Is there a sensor that might cause this kind of problem? How can I read the error codes from the ECU without a code scanner?