nasty exhaust smell
 

So for the past 2 weeks my cars been sitting outside because ive been waiting for a part and once i finally started it and brought it into the garage the exhaust smelt horrible.....almost like rotten eggs.


Is this possibly a clogged cat? I dont think any coolant is leaking because the oil is its normal color and exhaust color besides from being black the first 20-30 seconds after starting it was normal as well.

Any ideas? Only think i have replaced recently engine wise was the plugs with the Bosch Platinum 4+

Bad idea on the Bosch, they don't mix with GM.

Kitty cat.

for one, don't use any bosch parts in your alero. They suck with GM. Thats not your problem, but in a very short order you will be losing power and getting a hesitation with those plugs.

Check to make sure there are no dead animals laying on your exhaust that just got cooked. it happens, especially in the winter when they are looking for a warm place. :lol: Most likely a clogged cat though.

does it smell like sulfur?

^he said rotten eggs, so yes. thats what sulfur smells like.

reallly? bosch no good eh...well that sucks balls they were damned expensive...no animals around...im right in the middle down town of a big city...and the car for the most part has been sitting in the parking lot. It has 200k on it and from what i know the cats never been looked at/changed so i guess ill start with changing the cat first

that's what happens when you get talked into useless wallet-emptying plugs. platinums last slightly longer, but they don't perform any better. and you got the "+4". woo, it has 4 tips, as if that's going to do anything. electricity will always take the path of least resistance. it's no better than 1.

Gas sitting in the car leads to fuel in the injectors which clogs up the pipe and emmits smelly gas.

ahhhhhh that might be it too...its been at the same 1/4 tank of gas since the summer time im pretty sure...eff totally forgot about that

it's the cat, it's running really really rich, so change the cat... any MIL lights? if it runs good, take it for a drive and add some fresh gas and get the code read

nah no codes, i just remember seeing something about rotten egg smell and it not being a good thing. I imagine i should probably run some sort of fuel cleaner/injector cleaner when i get a fresh tank right?

Since it has 200K miles on it I would say it's the cat has gone bad.

Change your plugs then go take the car out for an Italian tune up.

are you having any other drivability issues? my alero has terrible smelling exhaust - since i bought it and it is fine. if anything, run a tank of gas through it, get it nice and warmed up, and go from there.

cant really tell of any drivability issues...normally its just started long enough to get the oil moving around then i pull it from the parking space into the garage and vice versa.. im replacing the cat tonight when i get home from work and hopefully taking it to get a fresh tank of gas....this weekend ill try taking it out on the highway to see how it does

Dumb question but did ya put your plug wires back on in the correct order? I did that once and it smelled like stinky ass

Have you driven it farther than just inside the garage? Get it good and warm and burn out your nasty gas and get back to us. That's a cat that isn't working well for sure, but it could be just because it's old and not warm. Give it a chance to light off and burn up some of the crap that's accumulated. If it still smells, it's toast.