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Cold engine shake

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?

Comments

  • edited January 2010
    It sounds like it's not firing on all cylinders when cold. That would likely be a fuel delivery problem. Does your vehicle have an engine block heater? If so use it and see if there is any difference.

    Also try some "gasline antifreeze" in your tank. You may have moisture in your gas.
  • edited January 2010
    No I don't have an Engine heater. I will have to try that. I was hoping to find out what "common" wear problems could arise from the abuse I have given my engine.
  • edited January 2010
    Running rough for a short time won't harm the engine. You should also have the ignition checked out. You need a good spark to "fire" those cylinders. The oil temperature won't matter, I have routinely started up cars at -30F. Just make sure the oil in the engine is light weight, 5W30 or less.

    Revving up the engine before the oil has circulated will cause excessive wear. A very cold start equals about 500 miles of normal driving in term of wear.
  • edited January 2010
    thank you for your help. So, as far as i can surmise I should be OK if i continue to drive the vehicle. The shaking is probably not related to a wear issue but an issue related to miss fire (gas line, spark problems) which I will have checked out. The car has never died at idle. I have also been reading about "safe" cold weather driving procedure, as far as I can tell as long as I drive the car gingerly until it warms up I should avoid adding a lot of engine wear. Does all of this sound ok?
  • edited January 2010
    You've go the picture. It's like jogging, don't start off by running fast until you're warmed up. Normal oil takes about 20-30 seconds to circulate to the valves, but heavy oil in cold weather may take several minutes!!!

    For smooth running you need a good spark, enough fuel and enough air to make a proper mixture. If your air filter has never been changed , I would change that too.

    Cold weather typically brings out all the weak points in your car.
  • edited January 2010
    Yes, basically you're on the right track.

    Warming up the engine is not necessary, although I'd wait maybe 30 seconds after the engine is running before driving in really cold weather.

    Driving gently is the best way, and the quickest, to warm up the engine. Remember, it's not just the engine that has to warm up. The transmission and drive train are freezing cold, too, and they need a few miles to warm up, just like the engine does.

    I don't think you've damaged the engine in any way. It's more likely it just needs some maintenance. Check the owner's manual and make sure any maintenance required at your current mileage has been done. If not, have everything brought up to date.
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