help? smoking shifter? smoking header?

[seeker]

i just recently finished a auto to manual swap on my 89 240sx. after driving it with open header- i noticed lots of whitish smoke coming up through the shifter hole. i thought this was because of no cat/no exhaust. so i put on a test pipe and put hte factory exhaust back on. after pushing the car a little, the car still spit out smoke however not as thick and not as much anymore. i remember i took the i think its the egr valve? off the downpipe and i thought may be the exhaust gas is seeping up through that hole. but i searched through the forums and it seems like this is a common problem. something about leakinging seals? i check it and there are no leaks.

anyone know or have any idea what this is? would plugging up that hole stop the smoke? car runs fine, just smokes a little. oh i opened the hood while it was smoking i noticed lots of steam or smoke coming from the exhaust manifold. is it just steam? i have no heat shields on btw. help?