Exhaust Fumes Smell

[yossarian247]

Hi,

This isn't a problem I've heard mentioned with the Auris before, but when starting from cold and setting off I often notice a pungent smell of exhaust fumes in the cabin for a few seconds. It seems to be sucked in through the heater as if I remember to switch the air blower off it doesn't happen.

My first thought was a leaking exhaust, so I got the garage I use for MOTs to put it up on the ramp and have a look. He spent half an hour or so checking over the exhaust, and looking for any signs of leakage from the manifold, but could find nothing wrong.

Has anyone any suggestions as to what could be the cause? It's not a major problem, but is quite unpleasant for a few seconds when first starting.

Nick

[alan333]

It could be the air con needing cleaned. You can buy aerosols in Halfords etc which you set off in the car with the heater on recirc. I've not used them myself but have read good reports.

[yossarian247]

Thanks for the suggestion, the aircon probably could do with a clean as I get the occasional smell from it too.

This is different though, very definitely partially combusted petrol, like running an old carburettor engine with the choke full out. You can smell it from outside the car too if you jump out quickly after the engine starts. Once the engine has been running for a few seconds it goes and the exhaust is then odourless.

I guess for whatever reason the engine is just running very rich immediately after starting. I've cleaned the MAF, which made no difference, and the air filter looks nice and clean. I'm going to try leaving the Battery disconnected for a while to see if making the ecu relearn it's settings does any good.

[superfast808]

Blocked cabin filter not filtering out the fumes? Have a look at it, its behind the glove box.

Its normal for a rich smell to come through when starting, but if it's excessive I'd look at the above first.

When I start my diesel version in the cold I often get the even worse scent of raw diesel through the vents!

[yossarian247]

Thanks I'll have a look at that. I notice it's possible to get an activated charcoal pollen filter for these too so I might give one of those a try.

I appreciate some smell is to be expected when starting from cold, but this is so strong passengers sometimes comment on it. I don't remember even the 1980s bangers I used to drive around in 25 years ago smelling as bad on a cold start!

Otherwise the car starts and runs perfectly, and on long runs with gentle driving I've been getting up to 45 mpg which for a 1.6 petrol suggests there isn't anything too seriously wrong with it. Some diesels I've owned in the past didn't do any better than that!

[yossarian247]

Just thought I'd post an update. It was a clogged and dirty pollen filter allowing fumes into the car. Changing the filter got rid of the smell, so thank you again for the suggestion. :-)