Maybe your coil is getting weak. Look into some new wires, cap, rotor. Check your connections for dirt & corrosion at the coil.Try flooring it just after you start cranking. That should stop it from flooding. You can bring the codes up by jumping the 2 terminals in the upper right-hand corner of the black connector just under the dash below the steering wheel (that's where it is on my Safari). A paperclip will do. Turn the key on. DO NOT start the engine. You should get 3 sets of flashes per code, the first being 12 ( 1 flash, break, 2 flashes, longer break)on your SES light. The 12 means the computer is working. A 43 would be 4 flashes, break, 3 flashes, longer break. Record what you get. After you get all of the codes it starts over with 12 again. Now all you have to do is find out what they mean. Your local GM dealer can tell you that. Not all codes stay in memory after you shut off your engine. Some can only be gotten while the engine is running under a fault condition. To clear the codes just pull the neg. wire off of the batt. for 10-15 sec. You should do that after you retrieve the codes so you don't get old info the next time you try to bring the up. Good luck.