Do you know what is wrong next to my pumkin plants? The new vines are producing leaves that are crinkled and really small....

The new vines are producing leaves that are crinkled and really small. There are dark and flimsy spots all over and the tips of the leaves are very elongated. It seem that even the older leaves and vines are becoming like that and nearby is no sign of aphids or any other pest.
Answers:    lack of light - the place you choosed is too menacing
("leaves elongated")

whe you water never water the leaves

Pumkins must be transplanted surrounded by big bases of home-
compost

If you still have some seed put them as I said in big
holes full of compost - water and cover next to
a transparent bowl or half plastic bottle mineral water -
simply 10
days - At any price choose an other location !!

Little bit late but not too late
Two possibilities.Hard to speak without being competent to see them...Over spray from something sprayed nearby that has undermined them, or what is more likely is some sort of fungal disease if you are sure there are no insects. There are fungicides you can spray, but I will share you, that it is very hard to stop it once it have gotten established.but you can try. Be sure to get the undersides and tops of the leaves, and the soil even, too. Has it been highly wet where you are? Fungal diseases thrive within moist conditons. If you water, try not to get the leaves raining, or use a soaker hose. Good Luck! Are you watering at night or morning? watering at night will permit mold take over. Try to water within the morning so the leaves can dry, also using a soaker hose instead of a sprayer will allow the water to soak into the ground instead getting the entire plant wet. you might also stipulation to improve the feeding. fertilize weekly. Good Luck