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Discussion Starter · #1 ·
Was out for a run in the car earlier and there was a distinct molten rubber whiff in the car. I stopped and looked outside and the smell was strong and seemed to be coming from underneath possibly by the exhaust somewhere along the length of it. Any one else had a similar issue with theirs?
 

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I think I'm correct in saying it's either due to yours being new and it's natural you'll get hot car smells, or it's the DPF regen which is again fine.
 

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Yeah it's most likely the DPF, especially if the fans are going full blast when you switch the engine off...

The burning smell worried me to when I first noticed it, why don't the dealers tell you about DPF on collection?
 

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Discussion Starter · #5 ·
Yeah the fans were going full chat after it's switched off! Going to google DPF now as that's a new one to me.
 

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Discussion Starter · #6 ·
Ok that all makes sense, worries over but your right this should be mentioned at hand over. Below is an extract I read which helped me understand it.

The passive regeneration occurs with no action taken by the car's computer. It occurs with higher sustained engine loads like freeway driving or fast acceleration onto the highway when exhaust gasses are hotter. These types of loads will produce exhaust gas temperatures (EGT) of about 350-500oC which thoroughly heat up and burn the DPF. If the car has only short stop-go trips, the exhaust doesn't have a chance to have a good passive burn off and will have more active regens or clog.

The active regeneration "self clean" occurs when filter soot loading is beyond 45% or every 466-621 miles (750-1000 kilometers), whichever is sooner. EGR is shut off and the fuel injectors squirt a little fuel into the engine cylinders after combustion (post combustion injection) that travels to the oxidation catalytic converter and oxidizes to raise EGT to around 600-650oC. The gasses travel to the DPF and burn up the trapped particulates.

During an active regen the car's computer also temporarily increases turbo boost about 2-4 psi to make up for any lost power. Engine rpm also goes up around 200 rpm on the 2.0L engine. A cycle lasts about 10 minutes and if you shut the engine off in the middle of an active regen cycle, you'll hear the radiator fans in the front of the car running fast (even after the car is shut off) and you may smell a burning rubber type odor. It will resume once you exceed 38 mph after the next engine start (and the exhaust is warm enough).

If the car still can't do an active regen and soot loading reaches 50-55%, it will try to force a 15 minute regen cycle. If you interrupt it by shutting the engine off, the active regen cycle won't finish. There is normally no light or indicator to show when the car is doing an active DPF cycle. If the cycle was interrupted by engine shut off, it'll try again before lighting the DPF warning light on the dashboard (pictured right). If that happens, drive at about 40 mph for at least 10 minutes in 4th or 5th gear at 2000RPM (Disclaimer: faster would be fine as long as you don't exceed the speed limit).
 

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Dealers just don't want 2 encourage hooligan mode,lol 😄
 
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