I have a 88 Corolla FX-G with a 5A-F engine, when I start it and its cold it starts fine but then it starts smoking and gets worse and worse, it smells real fumey but after driving for a few mins most of the smoke is gone. One of the spark plugs keeps going black after cleaning it. It also when I turn it off and take the key out keeps trying to go, dieseling? Have had compression tested and was ok so not sure what to try now???