Car cutting off randomly

lately my car has been cutting off randomly and jerks . and the check engine light is on, but it has been for months. it only shut off sometimes when i slow down or when i'm idle (like at a light or something). when it 1st happened earlier this yr. i was told i probably put some bad gas in my car and to get a gas treament but now its happening more frequent, seemingly everytime i put gas in my car. i'm a student so money is tight and its really scary not knowing when your car is gonna shut off or were you'll be...any advice

Welcome to Automotive Forums. Here's what you need to do. Take it to the auto parts store, either Autozone or Advance. They won't charge you to put a scanner on your computer to find out what is wrong. It's called pulling a code. Once you know what the code is, come back to Automotive Forums and let us know. Then, we can tell you how to fix your car.

ok. i went to advance auto and they did a diagnostic test and they only said that i probably needed a gas treatment. so i bought a ten dollar gas treatment and it still didnt work. i then went to a mechanic and he said my vacuum hose was slashed so i had it replaced but the problem is still there even thought the check engine light is now off. so is it possible i need a new fuel filter. it stalls at lights, when i slow down, and turns off when i sit for a while, and now white smoke is coming from my exhaust

ok. i went to advance auto and they did a diagnostic test and they only said that i probably needed a gas treatment. so i bought a ten dollar gas treatment and it still didnt work. i then went to a mechanic and he said my vacuum hose was slashed so i had it replaced but the problem is still there even thought the check engine light is now off. so is it possible i need a new fuel filter. it stalls at lights, when i slow down, and turns off when i sit for a while, and now white smoke is coming from my exhaust

So...what was the code they gave you?