2008 Nissan Maxima - Bad eggs

2008 Nissan Maxima se bad rotten egg smell while driving.

Bad catalytic converter can make this smell. Is your check engine light on?

A failing or over charging battery can make that smell.

Normally a catalytic converter issue .

I’d check if its coming from the exhaust. That’d be the catalytic converter not cleaning the exhaust. It could be a bad cat-conv, high fuel pressure (fuel regulator broken) or the engine running hot. Some are fixed by replacing the fuel filter (no idea why). If you smell it inside the car, check for an exhaust leak.

All the above came from the I-net. P.S. the car would fail an emissions test so hard the meter might peg.

A friend complained of similar. When I checked I thought it smelled more like dirty socks, and turned out to be a problem with the AC drain being plugged, combined w/ a small coolant leak.

Thanks so much!appreciate it. Will check out all those possibilities.


Just for future reference, new cats can also smell like this for awhile, so if you get the cat replaced and still smell it, don’t automatically assume something’s still wrong.

If need be can you replace w/a used catalytic converter or does it have to be new?

It doesn’t have to be new, but how can you be sure the replacement isn’t one tossed because it failed?

The exhaust might smell better with a new catalytic converter but I would first focus on keeping the exhaust out of the interior of the car.

Okay. Thanks!