Mitsubishi Repair: 91 Colt w/Mitsubishi Engine..weak in gear, wet/oily tail pipe/ good idle, head gasket, mitsubishi engine

Question
I can't figure it out. This car ran crappy a couple months ago, so i replaced the spark plugs. It became a brand new car in seconds, suddenly last week, it became weak again. Idles good, no knocking/ Put it in gear it shakes,rattles and rolls, runs barley, it's kicking out some very wet/oily muck out of the tail pipe, but the oil in the engine isn't pasty (I thought it may be a head gasket).Any ideas?
Thanks,
ian

Answer
Ian: a bad head gasket the smoke out the exhaust would be white in color, there would be water in the oil. Got that? The very wet,oily muck sounds like a bad ring or bad rings; so you are getting blow by. Other words the engine is just pushing the oil right pass the pistons(rings) and out the exhaust. You don't say if the car is using oil. Or if it is hotter than it should be. I would say if the engine is not running so good, weak like when you put it into gear and cause the engine to work. But sitting there just idles is easy on the engine. They often run good just sitting there, but when you want to drive the down the road. Then the engine can not do it, because of problems inside the engine. As too much oil passing the rings and blowing out the exhaust. Or if the smoke that is coming out is white and there is water in the oil, then the head gasket has blew out. Other wise I would say you need a ring job. You can have the engine tested to see if the rings are bad. Just find a shop to do this for you. It is a pressure test to see if things are holding or letting the oil pass. But then you would know. You know it is always better to rebuild the engine you have than get another one. Because you have no idea how someone else might have taken care of that other engine. And you know how you took care of your's. Wish I had better news for you. Hope this helps and good luck! Linda