gripples

All of sudden I started saying What the Hell, what is that smell? All searches said, Bad Cat, Bad Fuel Pump, Bad Fuel Filter, Bad Gas or an expensive combination. I use premium top tier gas. But, I was also having a problem with my 12V battery. I replaced the battery and Voila, NO MORE ROTTEN EGGS on the same tank of gas. I drive less than 15 miles a day. Could it be that the battery was diverting necessary amps from the Fuel Pump to cause the problem?

LuvmyLS

Diverting isn’t really the right way to look at this. This is odd because after the car starts, the alternator provides the power to run the car and charge the battery. Could have been a short in a cell of the battery. Also could be your alternator and your new battery is masking it.....for now. Did they do a charging system check?

greenskeep

Make sure your alternator isn’t over charging your new battery....over charge can lead to off gassing of a battery causing that smell.

user 710812323

Bad catalytic converters can give off a rotten egg smell.

How's your MPG?

greenskeep

correct, but he mention the smell when away after the battery swap so I suggest the out gassing battery possibility

user 710812323

That's what happens when I don't read the whole first post!😖

Tec80

100% the sulfur dioxide gas (aka rotten egg smell) was from the battery, which in the LS600 is at the left rear of the trunk. However, the battery was supposed to be the vent hose type - at the rear of the battery top there should be a little black tube that vents it outside the trunk. My bet is the old battery did not have that hose, or it wasn't connected.