Several issues with car-

This is a 2000 Contour that is a Bi-fuel car, but I only run it on gas. I figure I dont need a double rolling bomb. I am at a loss and almost out of money. Single mom here who has a very basic understanding of some car issues. My car wants to stall when at a stop upon accleration. It only does this intermitently. Car surges sometimes between 1 and 2nd gear on an auto tranny. Can smell a chemical exhaust smell, not like rotten eggs but like chemicals. It is using a ton of fuel, car is hotter than normal under hood, and it lacks power when I try to go faster. Also, the fuel gauge quit working after I put a bottle of fuel injection cleaner in my gas tank.I had the MAF senosr replaced and they replaced another sensor or air valve that was whistling. I had a sensor type part put on the tranny when it was shifting weird before. I just had the battery replace because it went dead. The Chevy dealer said the vacuum and elctronics were good. I do not have a check engine light but I did before they replaced the MAF sensor. The dea battery was the most recent part changed. I have spent 1400 on parts and labor and the car is still running the same. I took the Chevy mechanic for a test drive and it wouldnt anything until after I dropped him off. The mechanics think Im nutty but Im just very intune with my car. Please help, I am literally running out of money.