Hello,
I have looked around for a while on the site now and have come to the conclusion that there is no real answer for my question.

I have just recently bought a 2005 chevy malibu new body. the car runs rather well, and the outside looks great. However, the inside upholstery is in horrible shape. for lack of a better word, the upholstery has some rather "stubborn" black stains on it that i cannot remove. if i were to take my finger nail or a knife and gently rub on it, the substance (i believe to be some sort of dirt as the guy who owned it before worked in a steel mill) starts to come off. im worried about causing harm to the door if i scratch at it though.

does anyone have a possible solution to removal? i have tried the armour all cleaner and gotten the car detailed. i have heard that baby wipes work very well cause of the alcohol in them, however alcohol will dry out the upholstery. can anyone confirm or deny that this will work? if you have any questions feel free to ask, pictures available if needed. thanks ahead of time.

They make an upholstery spray foam you can try. I've heard good things with that. Otherwise get a carpet shampooer and see if that helps.

Is this on the plastic, leather or on cloth on the door?

if it is on the plastic and is near where arms or bare skin rubs it is most likely a mixture of dead skin and dirt (not to be gross but I have seen this from my own cars where I put my elbow every time I drive). I have always used a little bit of windex or simple green on a soft cloth and just scrubbed it off with no issues, after wards I clean it with water, dry it then use armor all or whatever you favorite interior detailing agent is.