I have a 91 Dodge spirit. It has 65000 miles on it. I have been driving my car in the early morning in sub-zero temperatures. recently the engine has been shaking erratically (even when warm) whenever i accelerate to slowly. I am worried that i may have damaged the engine. When i start the car I don't usually let it warm up before i start driving. I also have occasionally revved it to get going right after stating the car. I suppose the question is really what kind of damage may have resulted from running the engine with very cold oil. Could the shaking be a symptom of a larger problem I may have caused?