zakesm

Hi its zak from kenya. got a 1999 uk spec impreza turbo for about half a year now. has been running since new with LEADED fuel despite catalysts, as unleaded not available here. when the car is driven hard, there is a strong smell that comes from the car after it has been idled and switched off. smells a bit like an igniting match. i thought it was the catalysts all burned out, so i removed the centre catalyst DIY style, but the smell is still there. any ideas?

zak

korky

The sulphur-like smell is just the catalyst working hard - perfectly normal.

I'm not sure how long the cats will last if you are running it on leaded.

A full decat and remapping of the ECU is probably the best long-term way forward.

Cheers,

Korky

rav4640

knackerd cats mostly give out a rotten egg type smell, have you looked on the exhaust system for more cats, ie, one in the up pipe and another in the down pipe,

GUNNER

Hi Zak,

Check out the rocker cover gasket's ,they are known to leak dripping oil straight onto the up-pipe which create's strong smell inside and outside of car as the oil burn's off on the hot pipe.Just had mine replaced yesterday ,also had strong smell in/out of car. It will take 2/3 day,s to burn off excess oil before i know if this has cured it.

Just might be this!

MIKE....

ALX

There is nothing wrong with the cat if it smells of rotton eggs.....

It's Sulphur Dioxide - caused by sulphur in the fuel reacting in the catalyst (proof it works). That is why UK fuel is all now "Ultra Low Sulphur" to stop pollution of (toxic) sulphur dioxide from cars.

One thing to take note: If your running on Leaded - make sure the Oxygen sensor (sensor in the exhaust pipe after the turbo) is replaced/checked regulary as it will get contaminated by the leaded fuel.

ThrustSSC

Sorry to be pedantic, but rotten eggs is Hydrogen Sulphide. Sulphur Dioxide is best described as 'choking' - it feels like that when you inhale it.

They key driver for ULSP in the UK has been to enable direct fuel injection in petrol engines (like the diesel guys have been doing for years). Suplhur in the fuel causes problems with the injectors in such circumstances - and the governments/environmentalists are keen on direct injection because of the efficiency gains possible.

rav4640

had a cossie a few yrs back with cat, stank like hell , popped on a scorpion and stink went

[Edited by rav4640 - 1/19/2004 12:17:15 AM]

zakesm

thanks for your help guys. will get a de cat down pipe next time someone i know is coming down from engerland.

will check oxygen sensor too.

http://zak.carhirekenya.com

ALX

Opps got me SO2 mixed up with H2S

Yeah you get the H2S when there is little oxygen in the exhaust.

IIRC (this time!) It's the SO2 (sulphur dioxide) emissions were the biggest problem in diesels - and coal.

Still, reduce the sulphur content going in and you get less sulpur derivatives comming out (just other nasties instead )

zakesm

ok enough technical stuff. smells like eggs. its that catalyst. remove it. ok.

will my car pop and crackle a bit if both cats r out?

http://zak.carhirekenya.com