we recently bought a 30 year old ranch style home with a concrete block wall basement that leaked.With the water problem repaired We want to paint the walls,they already have paint on them. any suggestions on where to start?

My 10 year old Indiana house has a vented (unheated) crawlspace with 5 automatic vents. The earth is covered with plastic wrap that is not sealed against the walls or columns. The sub-floor has no insulation and the walls have 1” rigid foam insulation. A sump pump is installed at the lowest corner. This year, we started to get a musty and sour odor in the living space above the crawlspace for the first time. Our carpet is kept clean, we have no pets and no smokers. I had an expert examine it for mold and I was told it was dry and clean -- I checked it out myself and found nothing other than the unpleasant earthly smell. The expert recommended laying down a new plastic wrap which he recommended to be sealed tightly against the walls. He said the small gaps in the plastic wrap on the earth are causing water to evaporate and cause all this smell. I find this hard to believe, will a tightly sealed wrap solve this problem? Regardless, I have decided to lay down a new wrap according to the instructions he gave me. I still have a lot of questions though. - Should I keep the old plastic wrap and place the new one over it, or should I remove the old and install the new plastic wrap in its place? - Should I remove the rigid foam insulation on the walls to place the wraps on the walls behind them and then put them back on the wrap? - If that doesn’t stop the odor, will placing a plastic wrap directly on the sub-floors help control the odor from seeping into the living space? A friend noted this could be a recipe for mold on the sub-floors since it might trap moisture there. I appreciate any insights into this.