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Rotten egg smell....?

13K views 10 replies 6 participants last post by  DAHTcom 
#1 ·
Starting Sunday, I began to notice a smell somewhat like a rotten egg. I only really smell it at low speeds and with windows down. After today it was pretty strong, and Im now convinced it is coming from my car.

In the past (with my old sentra) that type of smell denoted something wrong with the CAT. Anyone here think that might be it?

The only thing to note, is something strange started to happen on Sunday morning. I parked the car while taking some pics, and a small puddle formed underneath the exhaust tip. You can see it in this picture (didnt notice it till I got home).

http://www.daht.com/underscore/images/auto/27.jpg

Gas mileage appears to be normal. I dont notice any power differences on the Butt Dyno, but I havent gotten on it hard yet this week (I know, I know, pretty pathetic eh). I feel like mentioning, even though I doubt its related, I let some grease monkeys at an oil and lube place, change the oil on Friday ::: sigh :::
 
#2 ·
I forgot to mention, It also has just over 18,000 miles. Im going to take it the stealership hopefully tomorrow to set up a time for them to look at it. For rightnow, Im assuming its the CAT, which blows if its bad that soon, but its my first ford, so welcome to ford eh?

Im just more concerned if that liquid from the tip is something to worry about. Ive had that happen up north when its cold out and such, but never in Arizona while its about 85-90 out still.
 
#3 ·
You prolly got gas somewhere that you usually don't or the place you got it from has a new supplier. What your smelling is sulfer. This is coming from the sulfer in your gas being super heated in the cat. It's normal and nothing to worry about. Try burning out this tank and getting your next fill up somewhere else. If it continues and get's worse there's a long shot chance that the converter is going south.
 
#6 ·
some bad mexican food? possibly too much green vegetables??
Ahahahahaha. Too funny!!! LOL

As far as gas goes... That is very possible. I havent gone to any new gas stations, but that doesnt mean they dont get a bad load of gas either. Thankfully, Im about a 1/4 tank now, so that will be resolved soon if thats the issue.
 
#7 ·
Given the fact that the initial post mentions having the oil changed by a shop...

The curious stain on the ground, in that pic, almost looks like an oil stain. That's just my interpretation, based on what I see on my monitor


However, I just might be babbling here, because I doubt that oil would get that far thru the exhaust, without you noticing any smoke. But, it could indicate that something is leaking, or is grossly overfilled.

Check the oil level, anyway, just to rule out the grease monkeys as a culprit.

In my experience, when my other Focus started smelling bad, it was because an O2 sensor had failed, and when it did, the ECU was compensating by making the mixture rich. The unburned fuel made the nasty stench, as it entered the CAT. It did this for a while (maybe the span of a week) before it threw a CEL/code. Prior to the CEL, I began to wonder why it the rotten smell lingered just after shutting it off.
 
#8 ·
In my experience, when my other Focus started smelling bad, it was because an O2 sensor had failed, and when it did, the ECU was compensating by making the mixture rich. The unburned fuel made the nasty stench, as it entered the CAT. It did this for a while (maybe the span of a week) before it threw a CEL/code. Prior to the CEL, I began to wonder why it the rotten smell lingered just after shutting it off.
Thanks for the post! I am wondering if that puddle could be gas, I havent seen it yet again, but I havent had a chance to since I looked closer at the picture.

Just wondering... Wouldnt the exhaust and piping be hot enough to ignite this if running super rich and backfire? That would definately explain the puddle under the bottom of the tip though.

I havent noticed any smoke at all. And Im doubting its oil, but you make a very good point. I will check in the AM if its possibly Oil. Either way I will be taking the car in tomrrow around 11am just to be sure.
 
#9 ·
Well they couldnt bring it in last friday, so I brang it in earlier today. Nine freaking AM, way to early to be up and about in my mind, Two PM is a nice round time to start the day I think. But as least I would get the car back the same day... or so I thought. Anyway, they have problems diagnosing the issue?

I hope this doesnt turn into a disastor, as they asked to keep it over night and work on it tomorrow again. Heard too many horror stories about cars left overnight there


If its not done by about 11am or so, Im gonna need a rental, and they were about to deny me that, hahaha... I dont think so. I dont want to be a jerk and tell them to hurry the heck up, but I dont want to use a rental either while my car sits in their hands :: sigh ::
 
#11 ·
LOL, another reason to worry I guess.. Hahahaah.. Believe it or not, as long as he doesnt screw something up, Its all good. (not really, ahah)

Well.. I dont smell the rotten egg smell anymore as of yet (only drove it back home and to a football game). Exhaust test found nothing, and some kind of fuel system test found nothing, so all they did was a PCM flash (hahaha). Well I probably shouldnt laugh yet, cause its not happening again yet. Car revs a little smoother now? I dunno anymore, guess Im just a little confused, but I will keep an eye on it.

Now when I start the car, the engine revs up to 2k or so for about 20 secs, then idles normally (didnt happen before, and not that Im worried about it)
 
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