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DISCUSSION => Engine + Driveline => Topic started by: Petebee on April 12, 2008, 11:40:58 PM

Title: My Car's Exhaust Stinks
Post by: Petebee on April 12, 2008, 11:40:58 PM

Really...I've noticed after driving when I get out I can smell a pretty strong sulphur-like smell coming from the car. Smells like a smoke bomb or firework smell.

Other than the stinky exhaust, the car runs and idles fine. It's an all stock 318i. Any ideas, or is this normal?

Title: My Car's Exhaust Stinks
Post by: PartsCar on April 13, 2008, 09:04:21 AM

i would check your O2 sensor. does your CEL have any stored codes?

Title: My Car's Exhaust Stinks
Post by: neilofla on April 13, 2008, 10:08:32 AM

This can be caused by a high sulphur content in the petrol you're using. I think the sulphur is oxidised in the catalytic converter, creating the smell.

Maybe if you switch to a low sulphur petrol it'll eliminate the smell. (Although I know if I asked for low sulphur petrol in my local garage, I'd get some very strange looks...)

High sulphur petrol caused a lot of problems in England during the late '90s where the sulphur damaged the cylinder bores of 6-cylinder 5-series. Our M42 engines aren't affected thankfully!

Title: My Car's Exhaust Stinks
Post by: dude8383 on April 13, 2008, 10:31:00 AM

Long shot, but I would make sure there are no exhaust leaks..

Title: My Car's Exhaust Stinks
Post by: Petebee on April 13, 2008, 10:49:29 AM

Quote from: dude8383;46903

Long shot, but I would make sure there are no exhaust leaks..

This could be it. Car has original exhaust that is so to speak a bit "raspy".

No check engine light. Should I check for codes anyway?

It could be the gas, but I've used separately Exxon and BP 93 octane in the past two tanks. Both tankfuls a bit stinky.

Title: My Car's Exhaust Stinks
Post by: Jak318 on April 13, 2008, 11:35:16 AM

A sulphur smell is usually the death throws of a Catalytic converter.

Title: My Car's Exhaust Stinks
Post by: hoevesruperd on April 13, 2008, 12:49:19 PM

when i changed my fuel pump i had the smell for about 2 days. that was just when i had bought the car. it had been running with a poor fuel pump for a while. when i installed the new one, the car had more power, could burn more fuel and so i guess it burned out all the residues accumulated in the exhaust. the smell didnt last

has the car been sleeping for a while? did you do any engine modifications?

Title: My Car's Exhaust Stinks
Post by: D. Clay on April 13, 2008, 01:16:04 PM

Sometimes on damp cold mornings ( 40-50 F. in Texas) I will get a really strong smell when I back out of the driveway and drive through the exhaust. It smells like cat piss!

Title: My Car's Exhaust Stinks
Post by: tjts1 on April 13, 2008, 07:58:50 PM

Quote from: Jak318;46906

A sulphur smell is usually the death throws of a Catalytic converter.

+1

Title: My Car's Exhaust Stinks
Post by: colin86325 on April 13, 2008, 08:05:39 PM

Quote from: Jak318;46906

A sulphur smell is usually the death throws of a Catalytic converter.

True.

Title: My Car's Exhaust Stinks
Post by: gearheadE30 on April 16, 2008, 03:10:15 PM

lol I think you killed the cat.