Fumes From Air-Conditioning?

[SandalsMan]

Hello all

I have had my new CT200h fSport for just over a month now, done a little over 1,000 miles and I am delighted with it.

However one issue I am getting is in the recent chilly mornings when the heating is kicking in with the air-con on Auto, I am noticing a slight but definite smell of fumes. I cannot make my mind up whether it is a hot rubber/plastic smell or whether it is exhaust fumes. I have tried turning the air-con off and then there is no odour, so it is definitely coming from there.

Is there any possibility it could be exhaust gases leaking into air-con? Any ideas before I go back to my dealer?

Regards

S-man

[Wass]

Just in case it is exhaust fumes, shouldnt you be leaving the fault diagnosis,to the dealers? This sounds like the sort of thing which the dealers should be collecting on the back of a trailer.Carbon monoxide is a killer. Dont take any risks with it.

[SandalsMan]

Just in case it is exhaust fumes, shouldnt you be leaving the fault diagnosis,to the dealers? This sounds like the sort of thing which the dealers should be collecting on the back of a trailer.Carbon monoxide is a killer. Dont take any risks with it.

Thanks Wass, I had thought about that but I want to make sure if exhaust gas in the air-con is possible first. It does smell like hot plastic more than exhaust gas.

[Wass]

Yes it is possible to have exhaust gases in the air conditioning. If there were to be an exhaust leak in the vicinity of the fresh air intake for the air conditioning there could be circumstances when you would get carbon monoxide into the cabin. The easiest way to set your mind at rest is to buy a house hold carbon monoxide sensor ( looks like a smoke detector but detects CO instead of ionisation) test the sensor by holding it close to the exhaust outlet . Having cleared the alarm, site the sensor inside the cabin and it will detect CO if there is any exhaust gases getting into the cabin.

I have to say that the instances of exhaust CO getting into the cabin of modern cars is very rare by design and the burning smell is most probably coming from other components of the car.

[SandalsMan]

Yes it is possible to have exhaust gases in the air conditioning. If there were to be an exhaust leak in the vicinity of the fresh air intake for the air conditioning there could be circumstances when you would get carbon monoxide into the cabin. The easiest way to set your mind at rest is to buy a house hold carbon monoxide sensor ( looks like a smoke detector but detects CO instead of ionisation) test the sensor by holding it close to the exhaust outlet . Having cleared the alarm, site the sensor inside the cabin and it will detect CO if there is any exhaust gases getting into the cabin.

I have to say that the instances of exhaust CO getting into the cabin of modern cars is very rare by design and the burning smell is most probably coming from other components of the car.

Thanks Wass, thats great advice. At least I will know whether or not it is exhaust fumes.

[SandalsMan]

After a long motorway run I am pretty sure I know where the fumes are coming from!

On a recent run down to London there were no fumes whatsoever from the air-con whilst I was on the M40 until I hit the London slow moving traffic when the fumes returned. I then pressed the recirculation switch and the fumes disappeared. It was the same on the way back; no fumes when fast moving and nothing close in front but as soon as I was moving slow with a car or van in front the fumes were there. I have concluded that my ventilation intake is sucking in exhaust fumes from the car in front.

I now press the recirculate button as soon as I hit traffic. A little strange but I am sure that is what is happening.

[mikeyv]

To confirm your diagnosis, try driving slowly without any other vehicles nearby.

I had lpg smell through my aircon, also cured by switching to recirc, then obviously by fixing the leak.

Again, it was much worse at slow speed.