How do you get rotting pumpkin smell out of the car? It liquefied and juice got into the car. Smells like a rotting corpse.
I use a very inexpensive cleaning product that removes lots of things. It's really quick and should remove your problem quickly. Take the brown bottle of hydrogen peroxide out of the medicine cabinet, pour a small amount on to the area where the pumpkin has saturated your vehicle. Pat with a paper towel, repeat until area is cleaned.
Clean up the spill of rotting pumpkin juice and ventilate the car.
Then use baking soda. It will help absorb any lingering smells. Sprinkled baking soda and let it sit. Then vacuum it out and if necessary, repeat the procedure several times.
Vinegar also absorbs bad smell very well.
When milk is accidentally spilt in the car, it can make for a persistent odor. This page is about cleaning sour milk smell in a car.
This is a page about cleaning rotten meat odors from a car. Meat accidentally left in the car can quickly become rotten and fill your car with a very bad odor.
This is a page about removing rotten seafood odors from a car. Food accidentally spilled or left in a hot car can quickly fill your vehicle with a really bad smell.