92 Prelude wont start when car is switched off
 

I have a 92 automatic prelude, sometimes when i have been out in the car turn it off and go to start it up again it wont start, and a green light with an S in it on the dash board flashes, usually after about 15 mins the car will start but the green light is sometimes still flashing and the car drives very sluggish, i think that the green light is also to do with the sports mode which i never have it in.

I have also had the immobilisor disconnected, as we was told that this was most likely the problem, but it's still doing it a year on.

This problem does not always happen only on the odd occasion.

Please someone must know what this problem could be, HELP ME OUT!!!!