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Rotten Egg, Sulfur Smell?

DBCooper13

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Has anyone else noticed a rotten egg/sulfur smell when they shut off the engine? I always heard this was normally the result of catalytic converters responding to leaded fuel but I've only used unleaded. Vehicle only has a couple of hundred miles on it.
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Zig

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Has anyone else noticed a rotten egg/sulfur smell when they shut off the engine? I always heard this was normally the result of catalytic converters responding to leaded fuel but I've only used unleaded. Vehicle only has a couple of hundred miles on it.
Does it respond sluggishly? E-brake locked - although different smell but smells can at times be relative. How’s the operating temps. If you melted a cat the engine will struggle like having a potato stuffed into the exhaust pipe and your temps will climb and be off the chart pretty quick.

edit: I will add this - new as in factory new will/may have an initial smell (basic burn in heat cycle) but it should not persist nor intensify.
 
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DukeCLR

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edit: I will add this - new as in factory new will/may have an initial smell (basic burn in heat cycle) but it should not persist nor intensify.
This. I had a cat pee smell for a bit, it came from heater when it first came on but it went away.
 

JoesProGTO

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Has anyone else noticed a rotten egg/sulfur smell when they shut off the engine? I always heard this was normally the result of catalytic converters responding to leaded fuel but I've only used unleaded. Vehicle only has a couple of hundred miles on it.
Often, that sulfur smell is from carbon from the cylinders getting into the catalytic converters (often after high rpm runs) but in a new car, carbon shouldn’t build up…🤷🏻
 

unk

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I've noticed it as well with my EB, and as mentioned above I usually caught it after doing some heavy footed acceleration. It comes and goes, not sure if its something I should be a bit more wary of over time, I've got about 5k miles on it
 


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This excess gas fouling your catalytic converters. Repeated cold starts can exacerbate this during open loop cycle as the engine is dumping gobs of fuel before entering closed loop. Moreover, with only a couple hundred miles your ecu is still learning your driving habits and will lean out fuel injection over time. If there is a problem you will get a check engine. Have fun
 
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DBCooper13

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Does it respond sluggishly? E-brake locked - although different smell but smells can at times be relative. How’s the operating temps. If you melted a cat the engine will struggle like having a potato stuffed into the exhaust pipe and your temps will climb and be off the chart pretty quick.

edit: I will add this - new as in factory new will/may have an initial smell (basic burn in heat cycle) but it should not persist nor intensify.
No, it runs fine.
 
 








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