Rotten egg smell.........

Hello

My 1994 Grand Am GT 3.1 engine with 55,000 miles has a rotten egg smell coming out the exhaust. The service light is still off. What could be causing it????????????

The smell is normal on GMC vehicles. You may have carbon build up. I can think of ways to fix this. 1) blow the carbon out by going on a hard heavy footed drive for about 2 hours , pedal to the metal only. 2) Take your pcv valve off the intake hose and get a glass of water , with the motor running put the pcv valve into the glass of water , be very fast when doing this so you dont suck to much at a time. 3) Buy a throttle body cleaner thats safe for your throttle body. Ask your dealer what is safe to use. Follow instructions on the can , should work fine. 4) Moto vac cleaning , take to a dealer that can do a moto vac , it cleans all you intake ports and should cost around $80. Any of these should work fine , try in the order i gave you so you can save money. Also , once youve blown the carbon out , your car will have more power and response like when it was brand new. Message me and tell me your progress.