service light

I was wondering if anyone knew what would cause cause it to come on when it does and i let of the gas pedal it acts like it cuts out chugging is a better term but when i press the gas pedal it still runs fine any suggestions on what might be the cause is apprecated.

I'm having a somewhat similar problem with my 88, It could be a few things, it could be your fuel injectors, or fuel line is clogged or not working properly(fuel related), you could have a vacuum leak... Check your fuel injectors, fuel pump,etc, and check for any vacuum leaks. I know i have to.