[Solved] ATS fuel cleaner fixed the sulfur smell in my 2006 Tundra
I purchased an 06 Tundra V8 with 96k miles a couple months ago and so far it's been a great truck. I'm still learning the quirks and idiosyncrasies of my vehicle, but there is one problem that's been bothering me. About a month ago, I started noticing a rotten egg or sulfur like smell after getting out of the vehicle. The odor seems to be the most pungent right after I turn off the engine and get outta the vehicle.
The existing battery was kinda old, so I replaced it thinking the smell could be leaking sulfur dioxide from the battery. It hasn't fixed the problem. I also ran some BG 44k fuel system cleaner and so far the smell seems to have decreased by a fair amount, but more driving will give me a better idea. There are no CEL's on the truck at all and the fuel trim is +/- 1%, so the engine seems to be running great.
Could the catalytic converters being going bad? Not sure what else it could be, but there's no data from the computer to indicate that the cats are not running efficiently.
Likely your cats are the source of your sulfur smell (likely why it was sold). But instead of just throwing new cats on, still need to figure out what is the cause. There are a number of things that could lead to the cats not functioning properly, incorrect timing, bad spark plugs, a malfunctioning oxygen sensor just to name a few. Find a good shop to diagnose/fix it.
Did some research. It's the oxygen sensors. The 2 upstream of the cat converters between the engine and converters need replaced. The downstream sensors rarely go bad. Here is what I found.
If a bad oxygen sensor disrupts the air to fuel ratio mixture, or too much fuel is injected into the engine, your vehicle's gas mileage will be reduced. This excess fuel in the engine can produce a sulfuric, rotten egg smell, and may even produce black smoke from the exhaust.
I would replace all the O2 or oxygen sensors with Denso sensors. I own a 2000 tundra since new for 22 years. 300k miles still running daily driver. The oxygen sensors fail quite often. I own a 2007 or second generation Tundra. The oxygen sensors never fail. My neighbor owns a first generation Tundra. He replaced all his oxygen sensors and his issues similar to yours went away. I bet someone put crappie cheap after market oxygen sensors in it. Might be cats but I doubt it. My 22 year old Tundra has original cats. No issues. My bet is both upstream o2 sensors. I'd just replace them all.
BG is great stuff. I use BG all the time all my cars.