Ford Cmax 05 - Foul odour

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Tue 15 Mar 2011 23:31
Ford Cmax 05 - Foul odour - BJT000

My first visit here so I'd appreciate the benefit of the joint wisdom that prevails.

Not regularly, but on several occasions over the last year or two, with the car running, the interior has suddenly filled with a foul odour - rotten eggs/fish type - which almost necessitates vacating the car. It lingers for days despite air fresheners and open windows. It doesn't build up it just suddenly emits like a schoolyard stink bomb has been dropped.

I'm not talking dead birds, spilled milk etc. This is definitely an emission from the vehicle. "Catalytic converter" has been offered as a reason but with no explanation other than "They do that sometimes".

Any advice/remedy please as I'm not even sure what a CC is or does.

Thanking you in anticipation.

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Wed 16 Mar 2011 07:58
Ford Cmax 05 - Foul odour - Dwight Van Driver

Air conditioning ?

Needs sweetening. Get it to a Fastfit for clean out and sanitised

dvd

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Wed 16 Mar 2011 09:15
Ford Cmax 05 - Foul odour - BJT000
Would the smell not be a more frequent feature?
It happens very intermittently but when it does it's extremely foul.
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Wed 16 Mar 2011 11:22
Ford Cmax 05 - Foul odour - davmal
The cat reduces unburnt, more harmful, compounds to safer compounds in the exhaust system. It uses a catalyst, a metal or compound which is an "attractive" site for this reaction to occur, however the temperature of the cat is important, as the reaction will progress more quickly at higher temperatures.
At lower temperatures the cat will adsorb sulphur compounds, which then at higher temperatures, will combine with hydrogen from unburnt hydrocarbons, to yield hydrogen sulphide gas, the characteristic of which is the rotten egg smell in lower concentrations (it is an unfortunate characteristic of hydrogen sulphide that in high (lethal) concentrations, it paralyses the sense of smell).
Don't know what the answer is, but I would think that getting up to working temperature quickly might be beneficial, or buying a diesel ;)
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Wed 16 Mar 2011 12:16
Ford Cmax 05 - Foul odour - injection doc

need to establish whether its the AC or the cat. If iuts the cat its easy to clean the ASC with a foaming anti fungi spary. I would suggest giving the car a quick italian tune up and see if you experince the same smell.

If you do you will know its the cat, now if you do lots of local trips the sulphur will build up in the cat and then when the cat become hotter you get a stench.

Different fuel brands can reduce it. If it continues and you think you do fair motoring them may be you have a managment issue where the mixture is suddenly enriched and that too will make the cat stink ! It wont always show as a fault code and only live data may show if the coolant sensor is suddenly telling the engine its lower temp than it is making it run too rich causing a real stink from the cat. If this was the rpoblem its not good to continue as it is.

Edited by injection doc on 16/03/2011 at 12:18

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Wed 16 Mar 2011 14:12
Ford Cmax 05 - Foul odour - TeeCee

That sounds like cat stench all right.

The interesting question here is since the generated Hydrogen Sulphide should be coming out of the tailpipe, how's it finding its way into the cabin........?

The only times I've ever experienced this is stuck in traffic when I get the output of someone else's catalyser through the vents before my finger reaches the "recirculate" button.

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Thu 17 Mar 2011 13:42
Ford Cmax 05 - Foul odour - SteveRob

Could it be the Pollen filter in the aircon needs changing, just a thought

SteveR

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Thu 17 Mar 2011 17:12
Ford Cmax 05 - Foul odour - Glaikit Wee Scunner {P}

With the doors closed, stand outside with engine running, is there a pong from the exhaust? If not it is from the air con. Clean as above.

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Thu 17 Mar 2011 17:12
Ford Cmax 05 - Foul odour - Glaikit Wee Scunner {P}

With the doors closed, stand outside with engine running, is there a pong from the exhaust? If not it is from the air con. Clean as above.

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Sat 26 Mar 2011 19:26
Ford Cmax 05 - Foul odour - hillman

Why not try an 'Italian tuneup'. Go bombing up the motorway for 30 miles and then back. Get everything hot. It sometimes works wonders.

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