After pulling the valve and resetting the check engine light, i drove the truck about 1 week and then the check engine light came back on. i haven't had a chance to have the codes pulled as i have to return to Auto Zone to get them to do it for me, I don't notice the smoke as i did before and its still to early to tell by the oil consumption, but i have started noticing that after i crank it after its been sitting about 4 days it starts but runs very bad for a min like it wants to go dead and a puff of smoke comes out. Any other time i crank it no smoke, however when driving it and coming to a stop it idles very low at around 400-500rpms and acts like it wants to go dead. In fact one evening i was returning home and i pulled up and before i could do anything, it just died! What could be causing this? The tech did talk me into adding a bottle of Lucus fuel treatment and I'm still on the same tank, therefore i didn't know if any of the issues I've mentioned may be associated with the cleaning of the treatment. Any help would be appreciated.