ok...94 formula 118k mi...ses light keeps coming on at low rpm's on the highway...65mph at around 1500 rpms...drove from lubbock to dallas and back this weekend and on the way down there it didnt come on once but i was goin 80+ the whole way...on the way back i had to back it down after a while due to the speed limit goin down at night and the abundance of cops...about 30-45 seconds after i got it down to 65 the ses came on. could this have anything to do with the egr being gone?...or am i gonna have to get a scan tool?

 

Yes, If you check for codes you would find a EGR related code. on GMs the EGR system is tested on decel at over 45 MPH if memory serves. you have a non OBD2 car so seting the engine light is a difficult thing to do unless somthing is realy wrong, in your case its because you disabled a emisions system