<DIV class=Kona iGs6W="true">I have a 1991 oldsmobile cutlass ciera 3.3 liter v6 with 95,000 miles. I just recently had the gas tank, sending unit and fuel filter replaced. Just recently I noticed a strong smell of gas when the car is running, it seems to come from the exhaust. There is only a smell when the car is running after the car is turned off the smell is gone. Is it possible the oxyen sensor is faulty causing the engine to run to rich??Any help with be appreciated.</DIV>

 

I WOULD IMMEDIATELY IF NOT SOONER PLACE THE CAR ON A LIFT AND GO UNDERNEATH WHILE THE CAR IS RUNNING AND LOOK FOR A LEAK. ( NO MATCHES PLEASE ) IF A LEAK IS NOT FOUND I WOULD LOOK UNDER THE HOOD WHILE THE ENGINE IS RUNNING FOR A LEAK. IF YOU SMELL GAS YOU HAVE A VERY SERIOUS SAFETY PROBLEM.. CHECK IT NOW..THE MECHANIC THAT HAD THE TANK REMOVED WOULD PROBABLY CHECK THAT END AT NO CHARGE BECAUSE HE WAS JUST THERE.. LIABILITY?????

 

If you just turn the key to the run position, without starting the car, the fuel pump will run and pressurize the fuel system. Then you can check for a leak without worrying about burning yourself on the exhaust.


If the smell is coming from the exhaust itself, it may be running too rich. An o2 sensor can cause this, but other things can also. A good mechanic can troubleshoot that. I would visually check for leaks first, though. That seems most likely.

 

I ALSO HAVE FOUND THAT A STOPPED UP CATALYTIC CONVERTER WILL CAUSE A FOUL ODOR. JUST A THOUGHT.

 

I HAVE ALSO FOUND THAT A DEFECTIVE CATALYTIC CONVERTER CAN CAUSE A FOUL ODOR. JUST A THOUGHT.