1994 Ford Escort

When I come to a stop, my Ford Escort Wagon XL sounds rough and when I apply the accelerator, the engine stops. The car sounds like it needs a tune up and I just had one 7 months ago. Lately when i'm on the freeway the "check engine" light on the dashboard is coming on. My one older brother knows more about mechanical work than I do. We replaced the vacuum hose (it had a few holes in it) and another hose next to it and replace the PVC valve. Still the car wants to konk out! How about if we replace the oxygen sensor? I don't have $300 - $375 to get it tuned up again! We checked the fuel filter out and that seems fine. Every time I come to a stop, the car sounds rough and wants to turn off. The "check engine" comes on every time the car wants to konk out. Your help is greatly appreciated.