 Intermittent Knocking under load
About a month ago my 1990 2.3 l automatic started occasionally making this fast paced knocking or ticking sound, it usually only does it under load u a hill or when giving it the gas, and it can go a whole week or so without doing it, the other day it did it on the interstate at night and i happened to notice out the driver mirror that it was blowing a lot of smoke out of the tailpipe, it went away after i crested the hill i was going u and didn't come back, and the smoke went away as well. sometimes when i start it up i will puff a little clout of smoke(white any help would be appreciated...btw it sounds like its coming from the head | 
